diff --git a/arch/arm/src/efm32/efm32_dma.c b/arch/arm/src/efm32/efm32_dma.c
index d568626b29..34a1520353 100644
--- a/arch/arm/src/efm32/efm32_dma.c
+++ b/arch/arm/src/efm32/efm32_dma.c
@@ -274,8 +274,8 @@ void weak_function up_dmainitialize(void)
 
   /* Initialize the channel list  */
 
-  sem_init(&g_dmac.exclsem, 0, 1);
-  sem_init(&g_dmac.chansem, 0, EFM32_DMA_NCHANNELS);
+  nxsem_init(&g_dmac.exclsem, 0, 1);
+  nxsem_init(&g_dmac.chansem, 0, EFM32_DMA_NCHANNELS);
 
   for (i = 0; i < EFM32_DMA_NCHANNELS; i++)
     {
diff --git a/arch/arm/src/efm32/efm32_i2c.c b/arch/arm/src/efm32/efm32_i2c.c
index 6b14038a77..964ecc4fcd 100644
--- a/arch/arm/src/efm32/efm32_i2c.c
+++ b/arch/arm/src/efm32/efm32_i2c.c
@@ -673,14 +673,14 @@ static inline void efm32_i2c_sem_post(FAR struct efm32_i2c_priv_s *priv)
 
 static inline void efm32_i2c_sem_init(FAR struct efm32_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/efm32/efm32_spi.c b/arch/arm/src/efm32/efm32_spi.c
index 01491669fd..13b3c1d220 100644
--- a/arch/arm/src/efm32/efm32_spi.c
+++ b/arch/arm/src/efm32/efm32_spi.c
@@ -1605,7 +1605,7 @@ static int spi_portinitialize(struct efm32_spidev_s *priv)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_EFM32_SPI_DMA
   /* Allocate two DMA channels... one for the RX and one for the TX side of
@@ -1639,8 +1639,8 @@ static int spi_portinitialize(struct efm32_spidev_s *priv)
 
   /* Initialized semaphores used to wait for DMA completion */
 
-  (void)sem_init(&priv->rxdmasem, 0, 0);
-  (void)sem_init(&priv->txdmasem, 0, 0);
+  (void)nxsem_init(&priv->rxdmasem, 0, 0);
+  (void)nxsem_init(&priv->txdmasem, 0, 0);
 
   /* These semaphores are used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/efm32/efm32_usbhost.c b/arch/arm/src/efm32/efm32_usbhost.c
index e3c8c548a7..866af2af7b 100644
--- a/arch/arm/src/efm32/efm32_usbhost.c
+++ b/arch/arm/src/efm32/efm32_usbhost.c
@@ -5155,8 +5155,8 @@ static inline void efm32_sw_initialize(FAR struct efm32_usbhost_s *priv)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -5186,7 +5186,7 @@ static inline void efm32_sw_initialize(FAR struct efm32_usbhost_s *priv)
        * have priority inheritance enabled.
        */
 
-      sem_init(&chan->waitsem,  0, 0);
+      nxsem_init(&chan->waitsem,  0, 0);
       sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
diff --git a/arch/arm/src/imx1/imx_spi.c b/arch/arm/src/imx1/imx_spi.c
index 695d6b358f..2f4d6bdd3e 100644
--- a/arch/arm/src/imx1/imx_spi.c
+++ b/arch/arm/src/imx1/imx_spi.c
@@ -1122,10 +1122,10 @@ FAR struct spi_dev_s *imx_spibus_initialize(int port)
    * signaling and, hence, should not have priority inheritance enabled.
    */
 
-   sem_init(&priv->waitsem, 0, 0);
+   nxsem_init(&priv->waitsem, 0, 0);
    sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
-   sem_init(&priv->exclsem, 0, 1);
+   nxsem_init(&priv->exclsem, 0, 1);
 
   /* Initialize control register: min frequency, ignore ready, master mode, mode=0, 8-bit */
 
diff --git a/arch/arm/src/imx6/imx_ecspi.c b/arch/arm/src/imx6/imx_ecspi.c
index 9b6b34ceff..9e94afa85e 100644
--- a/arch/arm/src/imx6/imx_ecspi.c
+++ b/arch/arm/src/imx6/imx_ecspi.c
@@ -1308,10 +1308,10 @@ FAR struct spi_dev_s *imx_spibus_initialize(int port)
    * signaling and, hence, should not have priority inheritance enabled.
    */
 
-   sem_init(&priv->waitsem, 0, 0);
+   nxsem_init(&priv->waitsem, 0, 0);
    sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
-   sem_init(&priv->exclsem, 0, 1);
+   nxsem_init(&priv->exclsem, 0, 1);
 
   /* Initialize control register: min frequency, ignore ready, master mode, mode=0, 8-bit */
 
diff --git a/arch/arm/src/kinetis/kinetis_i2c.c b/arch/arm/src/kinetis/kinetis_i2c.c
index 6efc2ff09a..d645de2553 100644
--- a/arch/arm/src/kinetis/kinetis_i2c.c
+++ b/arch/arm/src/kinetis/kinetis_i2c.c
@@ -316,13 +316,13 @@ static void kinetis_i2c_putreg(struct kinetis_i2cdev_s *priv, uint8_t value,
 
 static inline void kinetis_i2c_sem_init(FAR struct kinetis_i2cdev_s *priv)
 {
-  sem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->mutex, 0, 1);
 
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->wait, 0, 0);
   sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
 }
 
diff --git a/arch/arm/src/kinetis/kinetis_sdhc.c b/arch/arm/src/kinetis/kinetis_sdhc.c
index 4c8ffea18a..a1aa7209d4 100644
--- a/arch/arm/src/kinetis/kinetis_sdhc.c
+++ b/arch/arm/src/kinetis/kinetis_sdhc.c
@@ -2807,7 +2807,7 @@ FAR struct sdio_dev_s *sdhc_initialize(int slotno)
   /* Initialize the SDHC slot structure data structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/kinetis/kinetis_spi.c b/arch/arm/src/kinetis/kinetis_spi.c
index 1c25bc9754..3027c2a45f 100644
--- a/arch/arm/src/kinetis/kinetis_spi.c
+++ b/arch/arm/src/kinetis/kinetis_spi.c
@@ -1234,7 +1234,7 @@ FAR struct spi_dev_s *kinetis_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   return &priv->spidev;
 }
diff --git a/arch/arm/src/kl/kl_spi.c b/arch/arm/src/kl/kl_spi.c
index e9fb9947cd..bf64d1624e 100644
--- a/arch/arm/src/kl/kl_spi.c
+++ b/arch/arm/src/kl/kl_spi.c
@@ -689,7 +689,7 @@ FAR struct spi_dev_s *kl_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->spidev;
 }
 
diff --git a/arch/arm/src/lc823450/lc823450_adc.c b/arch/arm/src/lc823450/lc823450_adc.c
index 18721898b8..5c38dbfdd1 100644
--- a/arch/arm/src/lc823450/lc823450_adc.c
+++ b/arch/arm/src/lc823450/lc823450_adc.c
@@ -535,9 +535,9 @@ FAR struct adc_dev_s *lc823450_adcinitialize(void)
       inst->nchannels = CONFIG_ADC_NCHANNELS;
       inst->chanlist = lc823450_chanlist;
 
-      sem_init(&inst->sem_excl, 0, 1);
+      nxsem_init(&inst->sem_excl, 0, 1);
 #ifndef CONFIG_ADC_POLLED
-      sem_init(&inst->sem_isr, 0, 0);
+      nxsem_init(&inst->sem_isr, 0, 0);
 #endif
 
       lc823450_adc_sem_wait(inst);
diff --git a/arch/arm/src/lc823450/lc823450_dma.c b/arch/arm/src/lc823450/lc823450_dma.c
index 0e4f234236..104c1d2ac6 100644
--- a/arch/arm/src/lc823450/lc823450_dma.c
+++ b/arch/arm/src/lc823450/lc823450_dma.c
@@ -344,7 +344,7 @@ void up_dmainitialize(void)
       sq_init(&g_dma.phydmach[i].req_q);
     }
 
-  sem_init(&g_dma.exclsem, 0, 1);
+  nxsem_init(&g_dma.exclsem, 0, 1);
 
   if (irq_attach(LC823450_IRQ_DMAC, dma_interrupt, NULL) != 0)
     {
diff --git a/arch/arm/src/lc823450/lc823450_i2c.c b/arch/arm/src/lc823450/lc823450_i2c.c
index 5624f6f015..2366ae1f14 100644
--- a/arch/arm/src/lc823450/lc823450_i2c.c
+++ b/arch/arm/src/lc823450/lc823450_i2c.c
@@ -1114,9 +1114,9 @@ FAR struct i2c_master_s *lc823450_i2cbus_initialize(int port)
 
   if ((volatile int)priv->refs++ == 0)
     {
-      sem_init(&priv->sem_excl, 0, 1);
+      nxsem_init(&priv->sem_excl, 0, 1);
 #ifndef CONFIG_I2C_POLLED
-      sem_init(&priv->sem_isr, 0, 0);
+      nxsem_init(&priv->sem_isr, 0, 0);
 #endif
       (void)lc823450_i2c_init(priv, port);
     }
diff --git a/arch/arm/src/lc823450/lc823450_mtd.c b/arch/arm/src/lc823450/lc823450_mtd.c
index 03917f59ca..67b22ddba7 100644
--- a/arch/arm/src/lc823450/lc823450_mtd.c
+++ b/arch/arm/src/lc823450/lc823450_mtd.c
@@ -516,7 +516,7 @@ static FAR struct mtd_dev_s *lc823450_mtd_allocdev(uint32_t channel)
       return NULL;
     }
 
-  sem_init(&priv->sem, 0, 1);
+  nxsem_init(&priv->sem, 0, 1);
 
   priv->mtd.erase  = lc823450_erase;
   priv->mtd.bread  = lc823450_bread;
diff --git a/arch/arm/src/lc823450/lc823450_sdc.c b/arch/arm/src/lc823450/lc823450_sdc.c
index 24953a1c97..35e3238a90 100644
--- a/arch/arm/src/lc823450/lc823450_sdc.c
+++ b/arch/arm/src/lc823450/lc823450_sdc.c
@@ -644,7 +644,7 @@ int lc823450_sdc_locked(void)
 
   for (i = 0; i < 2; i++)
     {
-      (void)sem_getvalue(&_sdc_sem[i], &val);
+      (void)nxsem_getvalue(&_sdc_sem[i], &val);
       if (1 != val)
         {
           ret = 1;
diff --git a/arch/arm/src/lc823450/lc823450_sddrv_dep.c b/arch/arm/src/lc823450/lc823450_sddrv_dep.c
index 0d9a066f31..6ba4625db3 100644
--- a/arch/arm/src/lc823450/lc823450_sddrv_dep.c
+++ b/arch/arm/src/lc823450/lc823450_sddrv_dep.c
@@ -289,9 +289,9 @@ SINT_T sddep_os_init(struct SdDrCfg_s *cfg)
 
 #ifdef CONFIG_LC823450_SDC_DMA
   _hrdma[ch] = lc823450_dmachannel(DMA_CHANNEL_VIRTUAL);
-  sem_init(&_sem_rwait[ch], 0, 0);
+  nxsem_init(&_sem_rwait[ch], 0, 0);
   _hwdma[ch] = lc823450_dmachannel(DMA_CHANNEL_VIRTUAL);
-  sem_init(&_sem_wwait[ch], 0, 0);
+  nxsem_init(&_sem_wwait[ch], 0, 0);
 #endif /* CONFIG_LC823450_SDC_DMA */
   return 0;
 }
diff --git a/arch/arm/src/lc823450/lc823450_serial.c b/arch/arm/src/lc823450/lc823450_serial.c
index 1ba4745e04..7a15232f59 100644
--- a/arch/arm/src/lc823450/lc823450_serial.c
+++ b/arch/arm/src/lc823450/lc823450_serial.c
@@ -1317,12 +1317,12 @@ void up_serialinit(void)
 #ifdef TTYS1_DEV
   (void)uart_register("/dev/ttyS1", &TTYS1_DEV);
 #ifdef CONFIG_HSUART
-  sem_init(&g_uart1priv.txdma_wait, 0, 1);
+  nxsem_init(&g_uart1priv.txdma_wait, 0, 1);
   g_uart1priv.htxdma = lc823450_dmachannel(DMA_CHANNEL_UART1TX);
   lc823450_dmarequest(g_uart1priv.htxdma, DMA_REQUEST_UART1TX);
 
 
-  sem_init(&g_uart1priv.rxdma_wait, 0, 0);
+  nxsem_init(&g_uart1priv.rxdma_wait, 0, 0);
   g_uart1priv.hrxdma = lc823450_dmachannel(DMA_CHANNEL_UART1RX);
   lc823450_dmarequest(g_uart1priv.hrxdma, DMA_REQUEST_UART1RX);
 
diff --git a/arch/arm/src/lc823450/lc823450_spi.c b/arch/arm/src/lc823450/lc823450_spi.c
index 4104b84744..1f889b75a5 100644
--- a/arch/arm/src/lc823450/lc823450_spi.c
+++ b/arch/arm/src/lc823450/lc823450_spi.c
@@ -537,7 +537,7 @@ FAR struct spi_dev_s *lc823450_spibus_initialize(int port)
       modifyreg32(MRSTCNTAPB, 0, MRSTCNTAPB_PORT5_RSTB);
 
 #ifndef CONFIG_SPI_OWNBUS
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 #endif
 
       /* Initialize SPI mode. It must be done before starting SPI transfer */
@@ -556,7 +556,7 @@ FAR struct spi_dev_s *lc823450_spibus_initialize(int port)
       lc823450_spiinitialize();
 
 #ifdef CONFIG_LC823450_SPI_DMA
-      sem_init(&priv->dma_wait, 0, 0);
+      nxsem_init(&priv->dma_wait, 0, 0);
       priv->hdma = lc823450_dmachannel(DMA_CHANNEL_SIOTX);
       lc823450_dmarequest(priv->hdma, DMA_REQUEST_SIOTX);
 
diff --git a/arch/arm/src/lc823450/lc823450_timerisr.c b/arch/arm/src/lc823450/lc823450_timerisr.c
index ae478c476a..317819ad89 100644
--- a/arch/arm/src/lc823450/lc823450_timerisr.c
+++ b/arch/arm/src/lc823450/lc823450_timerisr.c
@@ -387,7 +387,7 @@ int up_hrttimer_usleep(unsigned int usec)
 {
   struct hrt_s hrt;
 
-  sem_init(&hrt.sem, 0, 0);
+  nxsem_init(&hrt.sem, 0, 0);
   hrt.usec = usec;
 
   hrt_usleep_add(&hrt);
diff --git a/arch/arm/src/lc823450/lc823450_usbdev.c b/arch/arm/src/lc823450/lc823450_usbdev.c
index 45de4e88fd..9d0e893aa7 100644
--- a/arch/arm/src/lc823450/lc823450_usbdev.c
+++ b/arch/arm/src/lc823450/lc823450_usbdev.c
@@ -1430,7 +1430,7 @@ void up_usbinitialize(void)
       return;
     }
 
-  sem_init(&dma_wait, 0, 0);
+  nxsem_init(&dma_wait, 0, 0);
   hdma = lc823450_dmachannel(DMA_CHANNEL_USBDEV);
   lc823450_dmarequest(hdma, DMA_REQUEST_USBDEV);
 
@@ -1697,7 +1697,7 @@ void usbdev_msc_read_enter()
   privep->epcmd &= ~USB_EPCMD_EMPTY_EN;
   epcmd_write(CONFIG_USBMSC_EPBULKIN, (privep->epcmd));
   lc823450_dmareauest_dir(hdma, DMA_REQUEST_USBDEV, 1);
-  sem_init(&dma_wait, 0, 0);
+  nxsem_init(&dma_wait, 0, 0);
 }
 
 /****************************************************************************
@@ -1800,7 +1800,7 @@ void usbdev_msc_write_enter0(void)
   privep->epcmd &= ~USB_EPCMD_READY_EN;
   epcmd_write(CONFIG_USBMSC_EPBULKOUT, (privep->epcmd));
   lc823450_dmareauest_dir(hdma, DMA_REQUEST_USBDEV, 0);
-  sem_init(&dma_wait, 0, 0);
+  nxsem_init(&dma_wait, 0, 0);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/lpc11xx/lpc11_i2c.c b/arch/arm/src/lpc11xx/lpc11_i2c.c
index b9d2d10743..1d2bd9a449 100644
--- a/arch/arm/src/lpc11xx/lpc11_i2c.c
+++ b/arch/arm/src/lpc11xx/lpc11_i2c.c
@@ -564,8 +564,8 @@ struct i2c_master_s *lpc11_i2cbus_initialize(int port)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->mutex, 0, 1);
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->wait, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc11xx/lpc11_spi.c b/arch/arm/src/lpc11xx/lpc11_spi.c
index c3f9157fe5..287cfb0632 100644
--- a/arch/arm/src/lpc11xx/lpc11_spi.c
+++ b/arch/arm/src/lpc11xx/lpc11_spi.c
@@ -579,7 +579,7 @@ FAR struct spi_dev_s *lpc11_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->spidev;
 }
 
diff --git a/arch/arm/src/lpc11xx/lpc11_ssp.c b/arch/arm/src/lpc11xx/lpc11_ssp.c
index a5a66d862a..faeb5ff1bc 100644
--- a/arch/arm/src/lpc11xx/lpc11_ssp.c
+++ b/arch/arm/src/lpc11xx/lpc11_ssp.c
@@ -993,7 +993,7 @@ FAR struct spi_dev_s *lpc11_sspbus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Enable the SPI */
 
diff --git a/arch/arm/src/lpc17xx/lpc17_gpdma.c b/arch/arm/src/lpc17xx/lpc17_gpdma.c
index 8fba6cbaad..7ef8384493 100644
--- a/arch/arm/src/lpc17xx/lpc17_gpdma.c
+++ b/arch/arm/src/lpc17xx/lpc17_gpdma.c
@@ -305,7 +305,7 @@ void weak_function up_dmainitialize(void)
 
   /* Initialize the DMA state structure */
 
-  sem_init(&g_gpdma.exclsem, 0, 1);
+  nxsem_init(&g_gpdma.exclsem, 0, 1);
 
   for (i = 0; i < LPC17_NDMACH; i++)
     {
diff --git a/arch/arm/src/lpc17xx/lpc17_i2c.c b/arch/arm/src/lpc17xx/lpc17_i2c.c
index 30763fe177..52d064a426 100644
--- a/arch/arm/src/lpc17xx/lpc17_i2c.c
+++ b/arch/arm/src/lpc17xx/lpc17_i2c.c
@@ -569,8 +569,8 @@ struct i2c_master_s *lpc17_i2cbus_initialize(int port)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->mutex, 0, 1);
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->wait, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc17xx/lpc17_sdcard.c b/arch/arm/src/lpc17xx/lpc17_sdcard.c
index 56ab096578..7260e7837e 100644
--- a/arch/arm/src/lpc17xx/lpc17_sdcard.c
+++ b/arch/arm/src/lpc17xx/lpc17_sdcard.c
@@ -2718,7 +2718,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the SD card slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc17xx/lpc17_spi.c b/arch/arm/src/lpc17xx/lpc17_spi.c
index 6ddef3951f..5d28258d4c 100644
--- a/arch/arm/src/lpc17xx/lpc17_spi.c
+++ b/arch/arm/src/lpc17xx/lpc17_spi.c
@@ -570,7 +570,7 @@ FAR struct spi_dev_s *lpc17_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->spidev;
 }
 
diff --git a/arch/arm/src/lpc17xx/lpc17_ssp.c b/arch/arm/src/lpc17xx/lpc17_ssp.c
index d66abf4d9d..7cdfbcfe78 100644
--- a/arch/arm/src/lpc17xx/lpc17_ssp.c
+++ b/arch/arm/src/lpc17xx/lpc17_ssp.c
@@ -982,7 +982,7 @@ FAR struct spi_dev_s *lpc17_sspbus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Enable the SPI */
 
diff --git a/arch/arm/src/lpc17xx/lpc17_usbhost.c b/arch/arm/src/lpc17xx/lpc17_usbhost.c
index 6bb48cd8f9..d5224b2e78 100644
--- a/arch/arm/src/lpc17xx/lpc17_usbhost.c
+++ b/arch/arm/src/lpc17xx/lpc17_usbhost.c
@@ -2267,7 +2267,7 @@ static int lpc17_epalloc(struct usbhost_driver_s *drvr,
        * should not have priority inheritance enabled.
        */
 
-      sem_init(&ed->wdhsem, 0, 0);
+      nxsem_init(&ed->wdhsem, 0, 0);
       sem_setprotocol(&ed->wdhsem, SEM_PRIO_NONE);
 
       /* Link the common tail TD to the ED's TD list */
@@ -3641,8 +3641,8 @@ struct usbhost_connection_s *lpc17_usbhost_initialize(int controller)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -3735,7 +3735,7 @@ struct usbhost_connection_s *lpc17_usbhost_initialize(int controller)
    * not have priority inheritance enabled.
    */
 
-  sem_init(&EDCTRL->wdhsem, 0, 0);
+  nxsem_init(&EDCTRL->wdhsem, 0, 0);
   sem_setprotocol(&EDCTRL->wdhsem, SEM_PRIO_NONE);
 
   /* Initialize user-configurable EDs */
diff --git a/arch/arm/src/lpc2378/lpc23xx_i2c.c b/arch/arm/src/lpc2378/lpc23xx_i2c.c
index 8191179f11..eebc910ef2 100644
--- a/arch/arm/src/lpc2378/lpc23xx_i2c.c
+++ b/arch/arm/src/lpc2378/lpc23xx_i2c.c
@@ -580,8 +580,8 @@ struct i2c_master_s *lpc2378_i2cbus_initialize(int port)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->mutex, 0, 1);
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->wait, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc2378/lpc23xx_spi.c b/arch/arm/src/lpc2378/lpc23xx_spi.c
index cf95f63a8b..55ec145335 100644
--- a/arch/arm/src/lpc2378/lpc23xx_spi.c
+++ b/arch/arm/src/lpc2378/lpc23xx_spi.c
@@ -582,7 +582,7 @@ FAR struct spi_dev_s *lpc23_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->spidev;
 }
 
diff --git a/arch/arm/src/lpc31xx/lpc31_ehci.c b/arch/arm/src/lpc31xx/lpc31_ehci.c
index 1884a41241..51becdda98 100644
--- a/arch/arm/src/lpc31xx/lpc31_ehci.c
+++ b/arch/arm/src/lpc31xx/lpc31_ehci.c
@@ -3937,7 +3937,7 @@ static int lpc31_epalloc(FAR struct usbhost_driver_s *drvr,
    * priority inheritance enabled.
    */
 
-  sem_init(&epinfo->iocsem, 0, 0);
+  nxsem_init(&epinfo->iocsem, 0, 0);
   sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
@@ -4920,8 +4920,8 @@ FAR struct usbhost_connection_s *lpc31_ehci_initialize(int controller)
 
   /* Initialize the EHCI state data structure */
 
-  sem_init(&g_ehci.exclsem, 0, 1);
-  sem_init(&g_ehci.pscsem,  0, 0);
+  nxsem_init(&g_ehci.exclsem, 0, 1);
+  nxsem_init(&g_ehci.pscsem,  0, 0);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -4931,7 +4931,7 @@ FAR struct usbhost_connection_s *lpc31_ehci_initialize(int controller)
 
   /* Initialize EP0 */
 
-  sem_init(&g_ehci.ep0.iocsem, 0, 1);
+  nxsem_init(&g_ehci.ep0.iocsem, 0, 1);
 
   /* Initialize the root hub port structures */
 
@@ -4970,7 +4970,7 @@ FAR struct usbhost_connection_s *lpc31_ehci_initialize(int controller)
        * should not have priority inheritance enabled.
        */
 
-      sem_init(&rhport->ep0.iocsem, 0, 0);
+      nxsem_init(&rhport->ep0.iocsem, 0, 0);
       sem_setprotocol(&rhport->iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
diff --git a/arch/arm/src/lpc31xx/lpc31_i2c.c b/arch/arm/src/lpc31xx/lpc31_i2c.c
index 8d79ac56e3..257ade4eb8 100644
--- a/arch/arm/src/lpc31xx/lpc31_i2c.c
+++ b/arch/arm/src/lpc31xx/lpc31_i2c.c
@@ -551,8 +551,8 @@ struct i2c_master_s *lpc31_i2cbus_initialize(int port)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->mutex, 0, 1);
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->wait, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc31xx/lpc31_spi.c b/arch/arm/src/lpc31xx/lpc31_spi.c
index 871eca69da..2c60c67e11 100644
--- a/arch/arm/src/lpc31xx/lpc31_spi.c
+++ b/arch/arm/src/lpc31xx/lpc31_spi.c
@@ -941,7 +941,7 @@ FAR struct spi_dev_s *lpc31_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Reset the SPI block */
 
diff --git a/arch/arm/src/lpc43xx/lpc43_ehci.c b/arch/arm/src/lpc43xx/lpc43_ehci.c
index e9bb3ddcdc..4979d9e825 100644
--- a/arch/arm/src/lpc43xx/lpc43_ehci.c
+++ b/arch/arm/src/lpc43xx/lpc43_ehci.c
@@ -3774,7 +3774,7 @@ static int lpc43_epalloc(FAR struct usbhost_driver_s *drvr,
    * should not have priority inheritance enabled.
    */
 
-  sem_init(&epinfo->iocsem, 0, 0);
+  nxsem_init(&epinfo->iocsem, 0, 0);
   sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
@@ -4751,8 +4751,8 @@ FAR struct usbhost_connection_s *lpc43_ehci_initialize(int controller)
 
   /* Initialize the EHCI state data structure */
 
-  sem_init(&g_ehci.exclsem, 0, 1);
-  sem_init(&g_ehci.pscsem,  0, 0);
+  nxsem_init(&g_ehci.exclsem, 0, 1);
+  nxsem_init(&g_ehci.pscsem,  0, 0);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -4762,7 +4762,7 @@ FAR struct usbhost_connection_s *lpc43_ehci_initialize(int controller)
 
   /* Initialize EP0 */
 
-  sem_init(&g_ehci.ep0.iocsem, 0, 1);
+  nxsem_init(&g_ehci.ep0.iocsem, 0, 1);
 
   /* Initialize the root hub port structures */
 
@@ -4801,7 +4801,7 @@ FAR struct usbhost_connection_s *lpc43_ehci_initialize(int controller)
        * not have priority inheritance enabled.
        */
 
-      sem_init(&rhport->ep0.iocsem, 0, 0);
+      nxsem_init(&rhport->ep0.iocsem, 0, 0);
       sem_setprotocol(&rhport->ep0.iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
diff --git a/arch/arm/src/lpc43xx/lpc43_gpdma.c b/arch/arm/src/lpc43xx/lpc43_gpdma.c
index 585bdb9db3..7175f9f40f 100644
--- a/arch/arm/src/lpc43xx/lpc43_gpdma.c
+++ b/arch/arm/src/lpc43xx/lpc43_gpdma.c
@@ -305,7 +305,7 @@ void weak_function up_dmainitialize(void)
 
   /* Initialize the DMA state structure */
 
-  sem_init(&g_gpdma.exclsem, 0, 1);
+  nxsem_init(&g_gpdma.exclsem, 0, 1);
 
   for (i = 0; i < LPC43_NDMACH; i++)
     {
diff --git a/arch/arm/src/lpc43xx/lpc43_i2c.c b/arch/arm/src/lpc43xx/lpc43_i2c.c
index fc0a25d1f1..763e03758c 100644
--- a/arch/arm/src/lpc43xx/lpc43_i2c.c
+++ b/arch/arm/src/lpc43xx/lpc43_i2c.c
@@ -526,8 +526,8 @@ struct i2c_master_s *lpc43_i2cbus_initialize(int port)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->mutex, 0, 1);
-  sem_init(&priv->wait, 0, 0);
+  nxsem_init(&priv->mutex, 0, 1);
+  nxsem_init(&priv->wait, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/lpc43xx/lpc43_spi.c b/arch/arm/src/lpc43xx/lpc43_spi.c
index 43e7e08052..093aaf6f2d 100644
--- a/arch/arm/src/lpc43xx/lpc43_spi.c
+++ b/arch/arm/src/lpc43xx/lpc43_spi.c
@@ -540,7 +540,7 @@ static FAR struct spi_dev_s *lpc43_spiport_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->spidev;
 }
 #endif /* CONFIG_LPC43_SPI */
diff --git a/arch/arm/src/lpc43xx/lpc43_ssp.c b/arch/arm/src/lpc43xx/lpc43_ssp.c
index c5af6124d5..4154bb9c0c 100644
--- a/arch/arm/src/lpc43xx/lpc43_ssp.c
+++ b/arch/arm/src/lpc43xx/lpc43_ssp.c
@@ -827,7 +827,7 @@ FAR struct spi_dev_s *lpc43_sspbus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Enable the SPI */
 
diff --git a/arch/arm/src/sam34/sam4cm_tc.c b/arch/arm/src/sam34/sam4cm_tc.c
index 32e465cc77..4ded41568a 100644
--- a/arch/arm/src/sam34/sam4cm_tc.c
+++ b/arch/arm/src/sam34/sam4cm_tc.c
@@ -748,7 +748,7 @@ static inline struct sam_chan_s *sam_tc_initialize(int channel)
       tmrerr("ERROR: Initializing TC%d\n", chconfig->chan);
 
       memset(chan, 0, sizeof(struct sam_chan_s));
-      sem_init(&chan->exclsem, 0, 1);
+      nxsem_init(&chan->exclsem, 0, 1);
       chan->base = chconfig->base;
       chan->pid  = chconfig->pid;
       chan->irq  = chconfig->irq;
diff --git a/arch/arm/src/sam34/sam_aes.c b/arch/arm/src/sam34/sam_aes.c
index 29634e69c7..ac9f0e70db 100644
--- a/arch/arm/src/sam34/sam_aes.c
+++ b/arch/arm/src/sam34/sam_aes.c
@@ -225,7 +225,7 @@ int aes_cypher(void *out, const void *in, uint32_t size, const void *iv,
 
 int up_aesinitialize()
 {
-  sem_init(&lock, 0, 1);
+  nxsem_init(&lock, 0, 1);
   sam_aes_enableclk();
   putreg32(AES_CR_SWRST, SAM_AES_CR);
   return OK;
diff --git a/arch/arm/src/sam34/sam_dmac.c b/arch/arm/src/sam34/sam_dmac.c
index 6cd36cacf8..b9ad29636f 100644
--- a/arch/arm/src/sam34/sam_dmac.c
+++ b/arch/arm/src/sam34/sam_dmac.c
@@ -1382,8 +1382,8 @@ void weak_function up_dmainitialize(void)
 
   /* Initialize semaphores */
 
-  sem_init(&g_chsem, 0, 1);
-  sem_init(&g_dsem, 0, CONFIG_SAM34_NLLDESC);
+  nxsem_init(&g_chsem, 0, 1);
+  nxsem_init(&g_dsem, 0, CONFIG_SAM34_NLLDESC);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/sam34/sam_hsmci.c b/arch/arm/src/sam34/sam_hsmci.c
index e59d558fe4..faad8051f6 100644
--- a/arch/arm/src/sam34/sam_hsmci.c
+++ b/arch/arm/src/sam34/sam_hsmci.c
@@ -2681,7 +2681,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the HSMCI slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sam34/sam_spi.c b/arch/arm/src/sam34/sam_spi.c
index 899eb9bc2e..58e4c94dca 100644
--- a/arch/arm/src/sam34/sam_spi.c
+++ b/arch/arm/src/sam34/sam_spi.c
@@ -1878,7 +1878,7 @@ struct spi_dev_s *sam_spibus_initialize(int port)
        * access to the SPI registers.
        */
 
-      sem_init(&spi->spisem, 0, 1);
+      nxsem_init(&spi->spisem, 0, 1);
       spi->initialized = true;
 
 #ifdef CONFIG_SAM34_SPI_DMA
@@ -1887,7 +1887,7 @@ struct spi_dev_s *sam_spibus_initialize(int port)
        * signaling and, hence, should not have priority inheritance enabled.
        */
 
-      sem_init(&spics->dmawait, 0, 0);
+      nxsem_init(&spics->dmawait, 0, 0);
       sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
diff --git a/arch/arm/src/sam34/sam_twi.c b/arch/arm/src/sam34/sam_twi.c
index 1b85275e8b..6663ca861c 100644
--- a/arch/arm/src/sam34/sam_twi.c
+++ b/arch/arm/src/sam34/sam_twi.c
@@ -967,8 +967,8 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->exclsem, 0, 1);
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sama5/sam_adc.c b/arch/arm/src/sama5/sam_adc.c
index 6688899510..044f9e8150 100644
--- a/arch/arm/src/sama5/sam_adc.c
+++ b/arch/arm/src/sama5/sam_adc.c
@@ -2025,7 +2025,7 @@ struct adc_dev_s *sam_adc_initialize(void)
 
       /* Initialize the private ADC device data structure */
 
-      sem_init(&priv->exclsem,  0, 1);
+      nxsem_init(&priv->exclsem,  0, 1);
       priv->cb  = NULL;
       priv->dev = &g_adcdev;
 
diff --git a/arch/arm/src/sama5/sam_can.c b/arch/arm/src/sama5/sam_can.c
index 029a4df1c6..b611767650 100644
--- a/arch/arm/src/sama5/sam_can.c
+++ b/arch/arm/src/sama5/sam_can.c
@@ -1947,7 +1947,7 @@ FAR struct can_dev_s *sam_caninitialize(int port)
       priv->freemb      = CAN_ALL_MAILBOXES;
       priv->initialized = true;
 
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 
       dev->cd_ops       = &g_canops;
       dev->cd_priv      = (FAR void *)priv;
diff --git a/arch/arm/src/sama5/sam_dmac.c b/arch/arm/src/sama5/sam_dmac.c
index a1002395db..49d110ed37 100644
--- a/arch/arm/src/sama5/sam_dmac.c
+++ b/arch/arm/src/sama5/sam_dmac.c
@@ -1879,8 +1879,8 @@ void sam_dmainitialize(struct sam_dmac_s *dmac)
 
   /* Initialize semaphores */
 
-  sem_init(&dmac->chsem, 0, 1);
-  sem_init(&dmac->dsem, 0, SAM_NDMACHAN);
+  nxsem_init(&dmac->chsem, 0, 1);
+  nxsem_init(&dmac->dsem, 0, SAM_NDMACHAN);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/sama5/sam_ehci.c b/arch/arm/src/sama5/sam_ehci.c
index 4070964863..d1d039c9c6 100644
--- a/arch/arm/src/sama5/sam_ehci.c
+++ b/arch/arm/src/sama5/sam_ehci.c
@@ -3758,7 +3758,7 @@ static int sam_epalloc(FAR struct usbhost_driver_s *drvr,
    * should not have priority inheritance enabled.
    */
 
-  sem_init(&epinfo->iocsem, 0, 0);
+  nxsem_init(&epinfo->iocsem, 0, 0);
   sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
@@ -4791,8 +4791,8 @@ FAR struct usbhost_connection_s *sam_ehci_initialize(int controller)
 
   /* Initialize the EHCI state data structure */
 
-  sem_init(&g_ehci.exclsem, 0, 1);
-  sem_init(&g_ehci.pscsem,  0, 0);
+  nxsem_init(&g_ehci.exclsem, 0, 1);
+  nxsem_init(&g_ehci.pscsem,  0, 0);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -4802,7 +4802,7 @@ FAR struct usbhost_connection_s *sam_ehci_initialize(int controller)
 
   /* Initialize EP0 */
 
-  sem_init(&g_ehci.ep0.iocsem, 0, 1);
+  nxsem_init(&g_ehci.ep0.iocsem, 0, 1);
 
   /* Initialize the root hub port structures */
 
@@ -4841,7 +4841,7 @@ FAR struct usbhost_connection_s *sam_ehci_initialize(int controller)
        * should not have priority inheritance enabled.
        */
 
-      sem_init(&rhport->ep0.iocsem, 0, 0);
+      nxsem_init(&rhport->ep0.iocsem, 0, 0);
       sem_setprotocol(&rhport->ep0.iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
diff --git a/arch/arm/src/sama5/sam_hsmci.c b/arch/arm/src/sama5/sam_hsmci.c
index 7b4cee4749..3acdc5b4d0 100644
--- a/arch/arm/src/sama5/sam_hsmci.c
+++ b/arch/arm/src/sama5/sam_hsmci.c
@@ -3298,7 +3298,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the HSMCI slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sama5/sam_nand.c b/arch/arm/src/sama5/sam_nand.c
index c7cf74f185..b5a2ec835e 100644
--- a/arch/arm/src/sama5/sam_nand.c
+++ b/arch/arm/src/sama5/sam_nand.c
@@ -2949,7 +2949,7 @@ struct mtd_dev_s *sam_nand_initialize(int cs)
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
 
@@ -2960,7 +2960,7 @@ struct mtd_dev_s *sam_nand_initialize(int cs)
       /* Initialize the global nand state structure */
 
 #if NAND_NBANKS > 1
-      sem_init(&g_nand.exclsem, 0, 1);
+      nxsem_init(&g_nand.exclsem, 0, 1);
 #endif
 
 #ifdef CONFIG_SAMA5_NAND_HSMCINTERRUPTS
@@ -2968,7 +2968,7 @@ struct mtd_dev_s *sam_nand_initialize(int cs)
        * have priority inheritance enabled.
        */
 
-      sem_init(&g_nand.waitsem, 0, 0);
+      nxsem_init(&g_nand.waitsem, 0, 0);
       sem_setprotocol(&g_nand.waitsem, SEM_PRIO_NONE);
 #endif
 
diff --git a/arch/arm/src/sama5/sam_ohci.c b/arch/arm/src/sama5/sam_ohci.c
index 8ecb6a0194..84f15f7351 100644
--- a/arch/arm/src/sama5/sam_ohci.c
+++ b/arch/arm/src/sama5/sam_ohci.c
@@ -2663,7 +2663,7 @@ static int sam_epalloc(struct usbhost_driver_s *drvr,
 
   /* Initialize the endpoint container */
 
-  sem_init(&eplist->wdhsem, 0, 0);
+  nxsem_init(&eplist->wdhsem, 0, 0);
 
   /* The wdhsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -3907,8 +3907,8 @@ struct usbhost_connection_s *sam_ohci_initialize(int controller)
 
   /* Initialize the state data structure */
 
-  sem_init(&g_ohci.pscsem,  0, 0);
-  sem_init(&g_ohci.exclsem, 0, 1);
+  nxsem_init(&g_ohci.pscsem,  0, 0);
+  nxsem_init(&g_ohci.exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sama5/sam_pmecc.c b/arch/arm/src/sama5/sam_pmecc.c
index 0339068c4f..a7275209b4 100644
--- a/arch/arm/src/sama5/sam_pmecc.c
+++ b/arch/arm/src/sama5/sam_pmecc.c
@@ -988,7 +988,7 @@ static int pmecc_pagelayout(uint16_t datasize, uint16_t eccsize)
 #if NAND_NPMECC_BANKS > 1
 void pmecc_initialize(void)
 {
-  sem_init(&g_pmecc.exclsem, 0, 1);
+  nxsem_init(&g_pmecc.exclsem, 0, 1);
 }
 #endif
 
diff --git a/arch/arm/src/sama5/sam_spi.c b/arch/arm/src/sama5/sam_spi.c
index cda2a36f97..7ca5159e44 100644
--- a/arch/arm/src/sama5/sam_spi.c
+++ b/arch/arm/src/sama5/sam_spi.c
@@ -1806,7 +1806,7 @@ struct spi_dev_s *sam_spibus_initialize(int port)
        * access to the SPI registers.
        */
 
-      sem_init(&spi->spisem, 0, 1);
+      nxsem_init(&spi->spisem, 0, 1);
       spi->initialized = true;
 
 #ifdef CONFIG_SAMA5_SPI_DMA
@@ -1815,7 +1815,7 @@ struct spi_dev_s *sam_spibus_initialize(int port)
        * signaling and, hence, should not have priority inheritance enabled.
        */
 
-      sem_init(&spics->dmawait, 0, 0);
+      nxsem_init(&spics->dmawait, 0, 0);
       sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
diff --git a/arch/arm/src/sama5/sam_ssc.c b/arch/arm/src/sama5/sam_ssc.c
index 8e4e66a032..b4351774ed 100644
--- a/arch/arm/src/sama5/sam_ssc.c
+++ b/arch/arm/src/sama5/sam_ssc.c
@@ -1037,7 +1037,7 @@ static void ssc_buf_initialize(struct sam_ssc_s *priv)
   int i;
 
   priv->freelist = NULL;
-  sem_init(&priv->bufsem, 0, CONFIG_SAMA5_SSC_MAXINFLIGHT);
+  nxsem_init(&priv->bufsem, 0, CONFIG_SAMA5_SSC_MAXINFLIGHT);
 
   for (i = 0; i < CONFIG_SAMA5_SSC_MAXINFLIGHT; i++)
     {
@@ -3430,7 +3430,7 @@ struct i2s_dev_s *sam_ssc_initialize(int port)
 
   /* Initialize the common parts for the SSC device structure  */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->dev.ops = &g_sscops;
   priv->sscno   = port;
 
diff --git a/arch/arm/src/sama5/sam_tc.c b/arch/arm/src/sama5/sam_tc.c
index 2bdff628ca..142d277ccd 100644
--- a/arch/arm/src/sama5/sam_tc.c
+++ b/arch/arm/src/sama5/sam_tc.c
@@ -971,7 +971,7 @@ static inline struct sam_chan_s *sam_tc_initialize(int channel)
       /* Initialize the timer counter data structure. */
 
       memset(tc, 0, sizeof(struct sam_tc_s));
-      sem_init(&tc->exclsem, 0, 1);
+      nxsem_init(&tc->exclsem, 0, 1);
       tc->base = tcconfig->base;
       tc->tc   = channel < 3 ? 0 : 1;
       tc->pid  = tcconfig->pid;
diff --git a/arch/arm/src/sama5/sam_trng.c b/arch/arm/src/sama5/sam_trng.c
index fed9a347ac..806815160f 100644
--- a/arch/arm/src/sama5/sam_trng.c
+++ b/arch/arm/src/sama5/sam_trng.c
@@ -356,8 +356,8 @@ static int sam_rng_initialize(void)
 
   /* Initialize semphores */
 
-  sem_init(&g_trngdev.exclsem, 0, 1);
-  sem_init(&g_trngdev.waitsem, 0, 0);
+  nxsem_init(&g_trngdev.exclsem, 0, 1);
+  nxsem_init(&g_trngdev.waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sama5/sam_tsd.c b/arch/arm/src/sama5/sam_tsd.c
index 403aa93f75..11e7649905 100644
--- a/arch/arm/src/sama5/sam_tsd.c
+++ b/arch/arm/src/sama5/sam_tsd.c
@@ -1674,7 +1674,7 @@ int sam_tsd_register(struct sam_adc_s *adc, int minor)
    * signaling and, hence, should not have priority inheritance enabled.
    */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 
   /* Register the device as an input device */
diff --git a/arch/arm/src/sama5/sam_twi.c b/arch/arm/src/sama5/sam_twi.c
index 117f29b445..f865104913 100644
--- a/arch/arm/src/sama5/sam_twi.c
+++ b/arch/arm/src/sama5/sam_twi.c
@@ -1268,8 +1268,8 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
   /* Initialize semaphores */
 
-  (void)sem_init(&priv->exclsem, 0, 1);
-  (void)sem_init(&priv->waitsem, 0, 0);
+  (void)nxsem_init(&priv->exclsem, 0, 1);
+  (void)nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/sama5/sam_xdmac.c b/arch/arm/src/sama5/sam_xdmac.c
index 458efcd82b..93ab306050 100644
--- a/arch/arm/src/sama5/sam_xdmac.c
+++ b/arch/arm/src/sama5/sam_xdmac.c
@@ -1906,8 +1906,8 @@ void sam_dmainitialize(struct sam_xdmac_s *xdmac)
 
   /* Initialize semaphores */
 
-  sem_init(&xdmac->chsem, 0, 1);
-  sem_init(&xdmac->dsem, 0, SAM_NDMACHAN);
+  nxsem_init(&xdmac->chsem, 0, 1);
+  nxsem_init(&xdmac->dsem, 0, SAM_NDMACHAN);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/samdl/sam_dmac.c b/arch/arm/src/samdl/sam_dmac.c
index 20501ecc0e..77763c5404 100644
--- a/arch/arm/src/samdl/sam_dmac.c
+++ b/arch/arm/src/samdl/sam_dmac.c
@@ -774,9 +774,9 @@ void weak_function up_dmainitialize(void)
 
   /* Initialize global semaphores */
 
-  sem_init(&g_chsem, 0, 1);
+  nxsem_init(&g_chsem, 0, 1);
 #if CONFIG_SAMDL_DMAC_NDESC > 0
-  sem_init(&g_dsem, 0, CONFIG_SAMDL_DMAC_NDESC);
+  nxsem_init(&g_dsem, 0, CONFIG_SAMDL_DMAC_NDESC);
 #endif
 
   /* Initialized the DMA channel table */
diff --git a/arch/arm/src/samdl/sam_i2c_master.c b/arch/arm/src/samdl/sam_i2c_master.c
index b377f1580a..ef07603e1f 100644
--- a/arch/arm/src/samdl/sam_i2c_master.c
+++ b/arch/arm/src/samdl/sam_i2c_master.c
@@ -1344,8 +1344,8 @@ struct i2c_master_s *sam_i2c_master_initialize(int bus)
   priv->dev.ops = &g_i2cops;
   priv->flags = 0;
 
-  (void)sem_init(&priv->exclsem, 0, 1);
-  (void)sem_init(&priv->waitsem, 0, 0);
+  (void)nxsem_init(&priv->exclsem, 0, 1);
+  (void)nxsem_init(&priv->waitsem, 0, 0);
 
   /* Perform repeatable I2C hardware initialization */
 
diff --git a/arch/arm/src/samv7/sam_hsmci.c b/arch/arm/src/samv7/sam_hsmci.c
index 544cae9524..7e5c0d0fe0 100644
--- a/arch/arm/src/samv7/sam_hsmci.c
+++ b/arch/arm/src/samv7/sam_hsmci.c
@@ -3330,7 +3330,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the HSMCI slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/samv7/sam_mcan.c b/arch/arm/src/samv7/sam_mcan.c
index 3abe2ce926..245bea0ee8 100644
--- a/arch/arm/src/samv7/sam_mcan.c
+++ b/arch/arm/src/samv7/sam_mcan.c
@@ -1441,7 +1441,7 @@ static void mcan_buffer_reserve(FAR struct sam_mcan_s *priv)
 
           flags = enter_critical_section();
           txfqs1 = mcan_getreg(priv, SAM_MCAN_TXFQS_OFFSET);
-          (void)sem_getvalue(&priv->txfsem, &sval);
+          (void)nxsem_getvalue(&priv->txfsem, &sval);
           txfqs2 = mcan_getreg(priv, SAM_MCAN_TXFQS_OFFSET);
 
           /* If the semaphore count and the TXFQS samples are in
@@ -1477,7 +1477,7 @@ static void mcan_buffer_reserve(FAR struct sam_mcan_s *priv)
           if (sval > 0)
             {
               canerr("ERROR: TX FIFOQ full but txfsem is %d\n", sval);
-              sem_reset(&priv->txfsem, 0);
+              nxsem_reset(&priv->txfsem, 0);
             }
         }
 
@@ -1542,7 +1542,7 @@ static void mcan_buffer_reserve(FAR struct sam_mcan_s *priv)
 
           /* Reset the semaphore count to the Tx FIFO free level. */
 
-          sem_reset(&priv->txfsem, tffl);
+          nxsem_reset(&priv->txfsem, tffl);
         }
 #endif
 
@@ -1587,7 +1587,7 @@ static void mcan_buffer_release(FAR struct sam_mcan_s *priv)
    * many times.
    */
 
-  (void)sem_getvalue(&priv->txfsem, &sval);
+  (void)nxsem_getvalue(&priv->txfsem, &sval);
   if (sval < priv->config->ntxfifoq)
     {
       sem_post(&priv->txfsem);
@@ -2270,7 +2270,7 @@ static void mcan_reset(FAR struct can_dev_s *dev)
    */
 
   sem_destroy(&priv->txfsem);
-  sem_init(&priv->txfsem, 0, config->ntxfifoq);
+  nxsem_init(&priv->txfsem, 0, config->ntxfifoq);
 
   /* Disable peripheral clocking to the MCAN controller */
 
@@ -2949,7 +2949,7 @@ static bool mcan_txready(FAR struct can_dev_s *dev)
    * the TX FIFO/queue.  Make sure that they are consistent.
    */
 
-  (void)sem_getvalue(&priv->txfsem, &sval);
+  (void)nxsem_getvalue(&priv->txfsem, &sval);
   DEBUGASSERT(((notfull && sval > 0) || (!notfull && sval <= 0)) &&
               (sval <= priv->config->ntxfifoq));
 #endif
@@ -3016,7 +3016,7 @@ static bool mcan_txempty(FAR struct can_dev_s *dev)
    * elements, then there is no transfer in progress.
    */
 
-  (void)sem_getvalue(&priv->txfsem, &sval);
+  (void)nxsem_getvalue(&priv->txfsem, &sval);
   DEBUGASSERT(sval > 0 && sval <= priv->config->ntxfifoq);
 
   empty = (sval ==  priv->config->ntxfifoq);
@@ -4014,8 +4014,8 @@ FAR struct can_dev_s *sam_mcan_initialize(int port)
 
       /* Initialize semaphores */
 
-      sem_init(&priv->locksem, 0, 1);
-      sem_init(&priv->txfsem, 0, config->ntxfifoq);
+      nxsem_init(&priv->locksem, 0, 1);
+      nxsem_init(&priv->txfsem, 0, config->ntxfifoq);
 
       dev->cd_ops  = &g_mcanops;
       dev->cd_priv = (FAR void *)priv;
diff --git a/arch/arm/src/samv7/sam_progmem.c b/arch/arm/src/samv7/sam_progmem.c
index 535817bdff..c04f18c860 100644
--- a/arch/arm/src/samv7/sam_progmem.c
+++ b/arch/arm/src/samv7/sam_progmem.c
@@ -363,7 +363,7 @@ void sam_progmem_initialize(void)
    * page buffer.
    */
 
-  sem_init(&g_page_sem, 0, 1);
+  nxsem_init(&g_page_sem, 0, 1);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/samv7/sam_qspi.c b/arch/arm/src/samv7/sam_qspi.c
index 3e51bee751..caf3b7c64f 100644
--- a/arch/arm/src/samv7/sam_qspi.c
+++ b/arch/arm/src/samv7/sam_qspi.c
@@ -1775,7 +1775,7 @@ struct qspi_dev_s *sam_qspi_initialize(int intf)
        * access to the QSPI registers.
        */
 
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_SAMV7_QSPI_DMA
       /* Pre-allocate DMA channels. */
@@ -1795,7 +1795,7 @@ struct qspi_dev_s *sam_qspi_initialize(int intf)
        * signaling and, hence, should not have priority inheritance enabled.
        */
 
-      sem_init(&priv->dmawait, 0, 0);
+      nxsem_init(&priv->dmawait, 0, 0);
       sem_setprotocol(&priv->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
diff --git a/arch/arm/src/samv7/sam_spi.c b/arch/arm/src/samv7/sam_spi.c
index 583cb7aca5..3e51b844ec 100644
--- a/arch/arm/src/samv7/sam_spi.c
+++ b/arch/arm/src/samv7/sam_spi.c
@@ -2162,7 +2162,7 @@ FAR struct spi_dev_s *sam_spibus_initialize(int port)
        * access to the SPI registers.
        */
 
-      sem_init(&spi->spisem, 0, 1);
+      nxsem_init(&spi->spisem, 0, 1);
       spi->escape_lastxfer = false;
       spi->initialized = true;
 
@@ -2172,7 +2172,7 @@ FAR struct spi_dev_s *sam_spibus_initialize(int port)
        * signaling and, hence, should not have priority inheritance enabled.
        */
 
-      sem_init(&spics->dmawait, 0, 0);
+      nxsem_init(&spics->dmawait, 0, 0);
       sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
diff --git a/arch/arm/src/samv7/sam_spi_slave.c b/arch/arm/src/samv7/sam_spi_slave.c
index 6b68769ab8..fe486b3428 100644
--- a/arch/arm/src/samv7/sam_spi_slave.c
+++ b/arch/arm/src/samv7/sam_spi_slave.c
@@ -1198,7 +1198,7 @@ struct spi_sctrlr_s *sam_spi_slave_initialize(int port)
        * access to the SPI registers.
        */
 
-      sem_init(&priv->spisem, 0, 1);
+      nxsem_init(&priv->spisem, 0, 1);
       priv->nss         = true;
       priv->initialized = true;
 
diff --git a/arch/arm/src/samv7/sam_ssc.c b/arch/arm/src/samv7/sam_ssc.c
index 11ae76c9f0..d7c7111fb7 100644
--- a/arch/arm/src/samv7/sam_ssc.c
+++ b/arch/arm/src/samv7/sam_ssc.c
@@ -1011,7 +1011,7 @@ static void ssc_buf_initialize(struct sam_ssc_s *priv)
   int i;
 
   priv->freelist = NULL;
-  sem_init(&priv->bufsem, 0, CONFIG_SAMV7_SSC_MAXINFLIGHT);
+  nxsem_init(&priv->bufsem, 0, CONFIG_SAMV7_SSC_MAXINFLIGHT);
 
   for (i = 0; i < CONFIG_SAMV7_SSC_MAXINFLIGHT; i++)
     {
@@ -3406,7 +3406,7 @@ struct i2s_dev_s *sam_ssc_initialize(int port)
 
   /* Initialize the common parts for the SSC device structure  */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->dev.ops = &g_sscops;
   priv->sscno   = port;
 
diff --git a/arch/arm/src/samv7/sam_tc.c b/arch/arm/src/samv7/sam_tc.c
index 91b0e36f5f..9bf28704fd 100644
--- a/arch/arm/src/samv7/sam_tc.c
+++ b/arch/arm/src/samv7/sam_tc.c
@@ -1187,7 +1187,7 @@ static inline struct sam_chan_s *sam_tc_initialize(int channel)
       /* Initialize the timer counter data structure. */
 
       memset(tc, 0, sizeof(struct sam_tc_s));
-      sem_init(&tc->exclsem, 0, 1);
+      nxsem_init(&tc->exclsem, 0, 1);
       tc->base = tcconfig->base;
       tc->tc   = tcconfig->tc;
 
diff --git a/arch/arm/src/samv7/sam_trng.c b/arch/arm/src/samv7/sam_trng.c
index e8eae34f99..f2649e50e6 100644
--- a/arch/arm/src/samv7/sam_trng.c
+++ b/arch/arm/src/samv7/sam_trng.c
@@ -357,8 +357,8 @@ static int sam_rng_initialize(void)
 
   /* Initialize semaphores */
 
-  sem_init(&g_trngdev.exclsem, 0, 1);
-  sem_init(&g_trngdev.waitsem, 0, 0);
+  nxsem_init(&g_trngdev.exclsem, 0, 1);
+  nxsem_init(&g_trngdev.waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/samv7/sam_twihs.c b/arch/arm/src/samv7/sam_twihs.c
index 05fa92cd71..c9a4e23c4f 100644
--- a/arch/arm/src/samv7/sam_twihs.c
+++ b/arch/arm/src/samv7/sam_twihs.c
@@ -1433,8 +1433,8 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
       /* Initialize semaphores */
 
-      (void)sem_init(&priv->exclsem, 0, 1);
-      (void)sem_init(&priv->waitsem, 0, 0);
+      (void)nxsem_init(&priv->exclsem, 0, 1);
+      (void)nxsem_init(&priv->waitsem, 0, 0);
 
       /* The waitsem semaphore is used for signaling and, hence, should not
        * have priority inheritance enabled.
diff --git a/arch/arm/src/samv7/sam_xdmac.c b/arch/arm/src/samv7/sam_xdmac.c
index cae694a68e..49db5ea719 100644
--- a/arch/arm/src/samv7/sam_xdmac.c
+++ b/arch/arm/src/samv7/sam_xdmac.c
@@ -1586,8 +1586,8 @@ void sam_dmainitialize(struct sam_xdmac_s *xdmac)
 
   /* Initialize semaphores */
 
-  sem_init(&xdmac->chsem, 0, 1);
-  sem_init(&xdmac->dsem, 0, SAMV7_NDMACHAN);
+  nxsem_init(&xdmac->chsem, 0, 1);
+  nxsem_init(&xdmac->dsem, 0, SAMV7_NDMACHAN);
 }
 
 /****************************************************************************
diff --git a/arch/arm/src/stm32/stm32_1wire.c b/arch/arm/src/stm32/stm32_1wire.c
index b43769577a..2fb86b112e 100644
--- a/arch/arm/src/stm32/stm32_1wire.c
+++ b/arch/arm/src/stm32/stm32_1wire.c
@@ -708,8 +708,8 @@ static int stm32_1wire_deinit(FAR struct stm32_1wire_priv_s *priv)
 
 static inline void stm32_1wire_sem_init(FAR struct stm32_1wire_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_isr, 0, 0);
 
   /* The sem_isr semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/stm32/stm32_aes.c b/arch/arm/src/stm32/stm32_aes.c
index 88e3a236c8..9c751c34d2 100644
--- a/arch/arm/src/stm32/stm32_aes.c
+++ b/arch/arm/src/stm32/stm32_aes.c
@@ -293,7 +293,7 @@ int up_aesinitialize(void)
 {
   uint32_t regval;
 
-  sem_init(&aes_lock, 0, 1);
+  nxsem_init(&aes_lock, 0, 1);
 
   regval = getreg32(STM32_RCC_AHBENR);
   regval |= RCC_AHBENR_AESEN;
diff --git a/arch/arm/src/stm32/stm32_bbsram.c b/arch/arm/src/stm32/stm32_bbsram.c
index f1e0b6d311..eba87b5f85 100644
--- a/arch/arm/src/stm32/stm32_bbsram.c
+++ b/arch/arm/src/stm32/stm32_bbsram.c
@@ -698,7 +698,7 @@ static int stm32_bbsram_probe(int *ent, struct stm32_bbsram_s pdev[])
 
           pdev[i].bbf = pf;
           pf = (struct bbsramfh_s *)((uint8_t *)pf + alloc);
-          sem_init(&g_bbsram[i].exclsem, 0, 1);
+          nxsem_init(&g_bbsram[i].exclsem, 0, 1);
         }
 
       avail -= alloc;
diff --git a/arch/arm/src/stm32/stm32_dma2d.c b/arch/arm/src/stm32/stm32_dma2d.c
index a6508f8245..327b050d63 100644
--- a/arch/arm/src/stm32/stm32_dma2d.c
+++ b/arch/arm/src/stm32/stm32_dma2d.c
@@ -2160,14 +2160,14 @@ int up_dma2dinitialize(void)
        * to the driver
        */
 
-      sem_init(&g_lock, 0, 1);
+      nxsem_init(&g_lock, 0, 1);
 
       /* Initialize the semaphore for interrupt handling.  This waitsem
        * semaphore is used for signaling and, hence, should not have
        * priority inheritance enabled.
        */
 
-      sem_init(g_interrupt.sem, 0, 0);
+      nxsem_init(g_interrupt.sem, 0, 0);
       sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
 #ifdef CONFIG_STM32_DMA2D_L8
diff --git a/arch/arm/src/stm32/stm32_hrtim.c b/arch/arm/src/stm32/stm32_hrtim.c
index 5d587188e4..d1bc279190 100644
--- a/arch/arm/src/stm32/stm32_hrtim.c
+++ b/arch/arm/src/stm32/stm32_hrtim.c
@@ -4802,7 +4802,7 @@ int hrtim_register(FAR const char *path, FAR struct hrtim_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->hd_closesem, 0, 1);
+  nxsem_init(&dev->hd_closesem, 0, 1);
 
   /* Register the HRTIM character driver */
 
diff --git a/arch/arm/src/stm32/stm32_i2c.c b/arch/arm/src/stm32/stm32_i2c.c
index 99b923eb15..d551810f9d 100644
--- a/arch/arm/src/stm32/stm32_i2c.c
+++ b/arch/arm/src/stm32/stm32_i2c.c
@@ -772,14 +772,14 @@ static inline void stm32_i2c_sem_post(struct stm32_i2c_priv_s *priv)
 
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32/stm32_i2c_alt.c b/arch/arm/src/stm32/stm32_i2c_alt.c
index 9c6ea4f831..6684059bbb 100644
--- a/arch/arm/src/stm32/stm32_i2c_alt.c
+++ b/arch/arm/src/stm32/stm32_i2c_alt.c
@@ -780,14 +780,14 @@ static inline void stm32_i2c_sem_post(FAR struct stm32_i2c_priv_s *priv)
 
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32/stm32_i2s.c b/arch/arm/src/stm32/stm32_i2s.c
index 60d4a8174b..8616119133 100644
--- a/arch/arm/src/stm32/stm32_i2s.c
+++ b/arch/arm/src/stm32/stm32_i2s.c
@@ -773,7 +773,7 @@ static void i2s_buf_initialize(struct stm32_i2s_s *priv)
   int i;
 
   priv->freelist = NULL;
-  sem_init(&priv->bufsem, 0, CONFIG_STM32_I2S_MAXINFLIGHT);
+  nxsem_init(&priv->bufsem, 0, CONFIG_STM32_I2S_MAXINFLIGHT);
 
   for (i = 0; i < CONFIG_STM32_I2S_MAXINFLIGHT; i++)
     {
@@ -2598,7 +2598,7 @@ FAR struct i2s_dev_s *stm32_i2sdev_initialize(int port)
 
   /* Initialize the common parts for the I2S device structure */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->dev.ops = &g_i2sops;
   priv->i2sno   = port;
 
diff --git a/arch/arm/src/stm32/stm32_ltdc.c b/arch/arm/src/stm32/stm32_ltdc.c
index 283bc92ef4..55dee088e9 100644
--- a/arch/arm/src/stm32/stm32_ltdc.c
+++ b/arch/arm/src/stm32/stm32_ltdc.c
@@ -1286,14 +1286,14 @@ static void stm32_global_configure(void)
 {
   /* Initialize the LTDC semaphore that enforces mutually exclusive access */
 
-  sem_init(&g_lock, 0, 1);
+  nxsem_init(&g_lock, 0, 1);
 
   /* Initialize the semaphore for interrupt handling.  This waitsem
    * semaphore is used for signaling and, hence, should not have priority
    * inheritance enabled.
    */
 
-  sem_init(g_interrupt.sem, 0, 0);
+  nxsem_init(g_interrupt.sem, 0, 0);
   sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
   /* Attach LTDC interrupt vector */
diff --git a/arch/arm/src/stm32/stm32_otgfshost.c b/arch/arm/src/stm32/stm32_otgfshost.c
index ed31cac037..3ef54e3cb5 100644
--- a/arch/arm/src/stm32/stm32_otgfshost.c
+++ b/arch/arm/src/stm32/stm32_otgfshost.c
@@ -5186,8 +5186,8 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -5217,7 +5217,7 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
        * have priority inheritance enabled.
        */
 
-      sem_init(&chan->waitsem,  0, 0);
+      nxsem_init(&chan->waitsem,  0, 0);
       sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
diff --git a/arch/arm/src/stm32/stm32_otghshost.c b/arch/arm/src/stm32/stm32_otghshost.c
index 1836808764..3d2c66df01 100644
--- a/arch/arm/src/stm32/stm32_otghshost.c
+++ b/arch/arm/src/stm32/stm32_otghshost.c
@@ -5189,8 +5189,8 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -5220,7 +5220,7 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
        * have priority inheritance enabled.
        */
 
-      sem_init(&chan->waitsem,  0, 0);
+      nxsem_init(&chan->waitsem,  0, 0);
       sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
diff --git a/arch/arm/src/stm32/stm32_rng.c b/arch/arm/src/stm32/stm32_rng.c
index 6d198341e3..b480e99a68 100644
--- a/arch/arm/src/stm32/stm32_rng.c
+++ b/arch/arm/src/stm32/stm32_rng.c
@@ -119,7 +119,7 @@ static int stm32_rng_initialize(void)
 
   memset(&g_rngdev, 0, sizeof(struct rng_dev_s));
 
-  sem_init(&g_rngdev.rd_devsem, 0, 1);
+  nxsem_init(&g_rngdev.rd_devsem, 0, 1);
 
   if (irq_attach(STM32_IRQ_RNG, stm32_interrupt, NULL))
     {
@@ -262,7 +262,7 @@ static ssize_t stm32_read(struct file *filep, char *buffer, size_t buflen)
        * enabled.
        */
 
-      sem_init(&g_rngdev.rd_readsem, 0, 0);
+      nxsem_init(&g_rngdev.rd_readsem, 0, 0);
       sem_setprotocol(&g_rngdev.rd_readsem, SEM_PRIO_NONE);
 
       g_rngdev.rd_buflen = buflen;
diff --git a/arch/arm/src/stm32/stm32_sdio.c b/arch/arm/src/stm32/stm32_sdio.c
index e5d3c22ecb..175d2127dc 100644
--- a/arch/arm/src/stm32/stm32_sdio.c
+++ b/arch/arm/src/stm32/stm32_sdio.c
@@ -2963,7 +2963,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the SDIO slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/stm32/stm32_spi.c b/arch/arm/src/stm32/stm32_spi.c
index 89859f6763..00ef10761f 100644
--- a/arch/arm/src/stm32/stm32_spi.c
+++ b/arch/arm/src/stm32/stm32_spi.c
@@ -1722,7 +1722,7 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_STM32_SPI_DMA
   /* Initialize the SPI semaphores that is used to wait for DMA completion.
@@ -1730,8 +1730,8 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->rxsem, 0, 0);
-  sem_init(&priv->txsem, 0, 0);
+  nxsem_init(&priv->rxsem, 0, 0);
+  nxsem_init(&priv->txsem, 0, 0);
 
   sem_setprotocol(&priv->rxsem, SEM_PRIO_NONE);
   sem_setprotocol(&priv->txsem, SEM_PRIO_NONE);
diff --git a/arch/arm/src/stm32/stm32f10xxx_dma.c b/arch/arm/src/stm32/stm32f10xxx_dma.c
index 65136a450f..4c7625b0f6 100644
--- a/arch/arm/src/stm32/stm32f10xxx_dma.c
+++ b/arch/arm/src/stm32/stm32f10xxx_dma.c
@@ -348,7 +348,7 @@ void weak_function up_dmainitialize(void)
   for (chndx = 0; chndx < DMA_NCHANNELS; chndx++)
     {
       dmach = &g_dma[chndx];
-      sem_init(&dmach->sem, 0, 1);
+      nxsem_init(&dmach->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/stm32/stm32f20xxx_dma.c b/arch/arm/src/stm32/stm32f20xxx_dma.c
index 6fb9d33cee..d1df805670 100644
--- a/arch/arm/src/stm32/stm32f20xxx_dma.c
+++ b/arch/arm/src/stm32/stm32f20xxx_dma.c
@@ -478,7 +478,7 @@ void weak_function up_dmainitialize(void)
   for (stream = 0; stream < DMA_NSTREAMS; stream++)
     {
       dmast = &g_dma[stream];
-      sem_init(&dmast->sem, 0, 1);
+      nxsem_init(&dmast->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/stm32/stm32f30xxx_i2c.c b/arch/arm/src/stm32/stm32f30xxx_i2c.c
index e779c040ed..d3e1326d71 100644
--- a/arch/arm/src/stm32/stm32f30xxx_i2c.c
+++ b/arch/arm/src/stm32/stm32f30xxx_i2c.c
@@ -888,14 +888,14 @@ static inline void stm32_i2c_sem_post(FAR struct stm32_i2c_priv_s *priv)
 
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32/stm32f33xxx_dma.c b/arch/arm/src/stm32/stm32f33xxx_dma.c
index af8601a0fb..d2852088ce 100644
--- a/arch/arm/src/stm32/stm32f33xxx_dma.c
+++ b/arch/arm/src/stm32/stm32f33xxx_dma.c
@@ -296,7 +296,7 @@ void weak_function up_dmainitialize(void)
   for (chndx = 0; chndx < DMA_NCHANNELS; chndx++)
     {
       dmach = &g_dma[chndx];
-      sem_init(&dmach->sem, 0, 1);
+      nxsem_init(&dmach->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/stm32/stm32f40xxx_dma.c b/arch/arm/src/stm32/stm32f40xxx_dma.c
index 54a0a97845..b6042790ad 100644
--- a/arch/arm/src/stm32/stm32f40xxx_dma.c
+++ b/arch/arm/src/stm32/stm32f40xxx_dma.c
@@ -477,7 +477,7 @@ void weak_function up_dmainitialize(void)
   for (stream = 0; stream < DMA_NSTREAMS; stream++)
     {
       dmast = &g_dma[stream];
-      sem_init(&dmast->sem, 0, 1);
+      nxsem_init(&dmast->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/stm32/stm32f40xxx_i2c.c b/arch/arm/src/stm32/stm32f40xxx_i2c.c
index ec5bc02d1e..be5627b4e4 100644
--- a/arch/arm/src/stm32/stm32f40xxx_i2c.c
+++ b/arch/arm/src/stm32/stm32f40xxx_i2c.c
@@ -829,14 +829,14 @@ static inline void stm32_i2c_sem_post(struct stm32_i2c_priv_s *priv)
 
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32f0/stm32f0_i2c.c b/arch/arm/src/stm32f0/stm32f0_i2c.c
index 69c5a1b53f..385db94d1d 100644
--- a/arch/arm/src/stm32f0/stm32f0_i2c.c
+++ b/arch/arm/src/stm32f0/stm32f0_i2c.c
@@ -829,14 +829,14 @@ static inline void stm32f0_i2c_sem_post(FAR struct stm32f0_i2c_priv_s *priv)
 
 static inline void stm32f0_i2c_sem_init(FAR struct stm32f0_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32f7/stm32_bbsram.c b/arch/arm/src/stm32f7/stm32_bbsram.c
index 62905f8326..0e615e6b5b 100644
--- a/arch/arm/src/stm32f7/stm32_bbsram.c
+++ b/arch/arm/src/stm32f7/stm32_bbsram.c
@@ -699,7 +699,7 @@ static int stm32_bbsram_probe(int *ent, struct stm32_bbsram_s pdev[])
 
           pdev[i].bbf = pf;
           pf = (struct bbsramfh_s *)((uint8_t *)pf + alloc);
-          sem_init(&g_bbsram[i].exclsem, 0, 1);
+          nxsem_init(&g_bbsram[i].exclsem, 0, 1);
         }
 
       avail -= alloc;
diff --git a/arch/arm/src/stm32f7/stm32_dma.c b/arch/arm/src/stm32f7/stm32_dma.c
index 92e8cb2437..ed3d02bb47 100644
--- a/arch/arm/src/stm32f7/stm32_dma.c
+++ b/arch/arm/src/stm32f7/stm32_dma.c
@@ -478,7 +478,7 @@ void weak_function up_dmainitialize(void)
   for (stream = 0; stream < DMA_NSTREAMS; stream++)
     {
       dmast = &g_dma[stream];
-      sem_init(&dmast->sem, 0, 1);
+      nxsem_init(&dmast->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/stm32f7/stm32_dma2d.c b/arch/arm/src/stm32f7/stm32_dma2d.c
index dcd5f7b8a2..233f6089ee 100644
--- a/arch/arm/src/stm32f7/stm32_dma2d.c
+++ b/arch/arm/src/stm32f7/stm32_dma2d.c
@@ -2152,14 +2152,14 @@ int up_dma2dinitialize(void)
        * to the driver
        */
 
-      sem_init(&g_lock, 0, 1);
+      nxsem_init(&g_lock, 0, 1);
 
       /* Initialize the semaphore for interrupt handling.  This waitsem
        * semaphore is used for signaling and, hence, should not have
        * priority inheritance enabled.
        */
 
-      sem_init(g_interrupt.sem, 0, 0);
+      nxsem_init(g_interrupt.sem, 0, 0);
       sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
 #ifdef CONFIG_STM32F7_DMA2D_L8
diff --git a/arch/arm/src/stm32f7/stm32_i2c.c b/arch/arm/src/stm32f7/stm32_i2c.c
index 1b5600b5e9..ec287e24ea 100644
--- a/arch/arm/src/stm32f7/stm32_i2c.c
+++ b/arch/arm/src/stm32f7/stm32_i2c.c
@@ -1074,14 +1074,14 @@ static inline void stm32_i2c_sem_post(FAR struct i2c_master_s *dev)
 
 static inline void stm32_i2c_sem_init(FAR struct i2c_master_s *dev)
 {
-  sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl, 0, 1);
+  nxsem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, 0, 0);
+  nxsem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, 0, 0);
   sem_setprotocol(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32f7/stm32_ltdc.c b/arch/arm/src/stm32f7/stm32_ltdc.c
index 218546a883..897a354681 100644
--- a/arch/arm/src/stm32f7/stm32_ltdc.c
+++ b/arch/arm/src/stm32f7/stm32_ltdc.c
@@ -1285,14 +1285,14 @@ static void stm32_global_configure(void)
 {
   /* Initialize the LTDC semaphore that enforces mutually exclusive access */
 
-  sem_init(&g_lock, 0, 1);
+  nxsem_init(&g_lock, 0, 1);
 
   /* Initialize the semaphore for interrupt handling.  This waitsem
    * semaphore is used for signaling and, hence, should not have priority
    * inheritance enabled.
    */
 
-  sem_init(g_interrupt.sem, 0, 0);
+  nxsem_init(g_interrupt.sem, 0, 0);
   sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
   /* Attach LTDC interrupt vector */
diff --git a/arch/arm/src/stm32f7/stm32_otghost.c b/arch/arm/src/stm32f7/stm32_otghost.c
index 59d8bd076e..b7d259a6d7 100644
--- a/arch/arm/src/stm32f7/stm32_otghost.c
+++ b/arch/arm/src/stm32f7/stm32_otghost.c
@@ -5183,8 +5183,8 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -5214,7 +5214,7 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
        * have priority inheritance enabled.
        */
 
-      sem_init(&chan->waitsem,  0, 0);
+      nxsem_init(&chan->waitsem,  0, 0);
       sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
diff --git a/arch/arm/src/stm32f7/stm32_rng.c b/arch/arm/src/stm32f7/stm32_rng.c
index 7b746dc522..df6e759abf 100644
--- a/arch/arm/src/stm32f7/stm32_rng.c
+++ b/arch/arm/src/stm32f7/stm32_rng.c
@@ -118,7 +118,7 @@ static int stm32_rng_initialize(void)
 
   memset(&g_rngdev, 0, sizeof(struct rng_dev_s));
 
-  sem_init(&g_rngdev.rd_devsem, 0, 1);
+  nxsem_init(&g_rngdev.rd_devsem, 0, 1);
 
   if (irq_attach(STM32_IRQ_RNG, stm32_rnginterrupt, NULL))
     {
@@ -283,7 +283,7 @@ static ssize_t stm32_rngread(struct file *filep, char *buffer, size_t buflen)
        * enabled.
        */
 
-      sem_init(&g_rngdev.rd_readsem, 0, 0);
+      nxsem_init(&g_rngdev.rd_readsem, 0, 0);
       sem_setprotocol(&g_rngdev.rd_readsem, SEM_PRIO_NONE);
 
       g_rngdev.rd_buflen = buflen;
diff --git a/arch/arm/src/stm32f7/stm32_sdmmc.c b/arch/arm/src/stm32f7/stm32_sdmmc.c
index 49a70d63fa..d64fd739a6 100644
--- a/arch/arm/src/stm32f7/stm32_sdmmc.c
+++ b/arch/arm/src/stm32f7/stm32_sdmmc.c
@@ -3204,7 +3204,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the SDIO slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/stm32f7/stm32_spi.c b/arch/arm/src/stm32f7/stm32_spi.c
index d6b4cb9e9c..c379bbf04b 100644
--- a/arch/arm/src/stm32f7/stm32_spi.c
+++ b/arch/arm/src/stm32f7/stm32_spi.c
@@ -1696,7 +1696,7 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access. */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_STM32F7_SPI_DMA
   /* Initialize the SPI semaphores that is used to wait for DMA completion.
@@ -1704,8 +1704,8 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->rxsem, 0, 0);
-  sem_init(&priv->txsem, 0, 0);
+  nxsem_init(&priv->rxsem, 0, 0);
+  nxsem_init(&priv->txsem, 0, 0);
 
   sem_setprotocol(&priv->rxsem, SEM_PRIO_NONE);
   sem_setprotocol(&priv->txsem, SEM_PRIO_NONE);
diff --git a/arch/arm/src/stm32l4/stm32l4_i2c.c b/arch/arm/src/stm32l4/stm32l4_i2c.c
index 47597c875b..1b22fc2477 100644
--- a/arch/arm/src/stm32l4/stm32l4_i2c.c
+++ b/arch/arm/src/stm32l4/stm32l4_i2c.c
@@ -862,14 +862,14 @@ static inline void stm32l4_i2c_sem_post(FAR struct stm32l4_i2c_priv_s *priv)
 
 static inline void stm32l4_i2c_sem_init(FAR struct stm32l4_i2c_priv_s *priv)
 {
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->sem_isr, 0, 0);
+  nxsem_init(&priv->sem_isr, 0, 0);
   sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/stm32l4/stm32l4_otgfshost.c b/arch/arm/src/stm32l4/stm32l4_otgfshost.c
index aadae1721c..b648379227 100644
--- a/arch/arm/src/stm32l4/stm32l4_otgfshost.c
+++ b/arch/arm/src/stm32l4/stm32l4_otgfshost.c
@@ -5189,8 +5189,8 @@ static inline void stm32l4_sw_initialize(FAR struct stm32l4_usbhost_s *priv)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->pscsem,  0, 0);
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->pscsem,  0, 0);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* The pscsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -5220,7 +5220,7 @@ static inline void stm32l4_sw_initialize(FAR struct stm32l4_usbhost_s *priv)
        * have priority inheritance enabled.
        */
 
-      sem_init(&chan->waitsem,  0, 0);
+      nxsem_init(&chan->waitsem,  0, 0);
       sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
diff --git a/arch/arm/src/stm32l4/stm32l4_qspi.c b/arch/arm/src/stm32l4/stm32l4_qspi.c
index be7cbd3769..57202ec4c2 100644
--- a/arch/arm/src/stm32l4/stm32l4_qspi.c
+++ b/arch/arm/src/stm32l4/stm32l4_qspi.c
@@ -2487,7 +2487,7 @@ struct qspi_dev_s *stm32l4_qspi_initialize(int intf)
        * access to the QSPI registers.
        */
 
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_STM32L4_QSPI_DMA
       /* Pre-allocate DMA channels. */
@@ -2507,7 +2507,7 @@ struct qspi_dev_s *stm32l4_qspi_initialize(int intf)
        * signaling and, hence, should not have priority inheritance enabled.
        */
 
-      sem_init(&priv->dmawait, 0, 0);
+      nxsem_init(&priv->dmawait, 0, 0);
       sem_setprotocol(&priv->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
@@ -2535,7 +2535,7 @@ struct qspi_dev_s *stm32l4_qspi_initialize(int intf)
        * priority inheritance enabled.
        */
 
-      sem_init(&priv->op_sem, 0, 0);
+      nxsem_init(&priv->op_sem, 0, 0);
       sem_setprotocol(&priv->op_sem, SEM_PRIO_NONE);
 #endif
 
diff --git a/arch/arm/src/stm32l4/stm32l4_rng.c b/arch/arm/src/stm32l4/stm32l4_rng.c
index 3334d86ec0..0ca0f52a30 100644
--- a/arch/arm/src/stm32l4/stm32l4_rng.c
+++ b/arch/arm/src/stm32l4/stm32l4_rng.c
@@ -115,7 +115,7 @@ static int stm32l4_rng_initialize(void)
 
   memset(&g_rngdev, 0, sizeof(struct rng_dev_s));
 
-  sem_init(&g_rngdev.rd_devsem, 0, 1);
+  nxsem_init(&g_rngdev.rd_devsem, 0, 1);
 
   if (irq_attach(STM32L4_IRQ_RNG, stm32l4_rnginterrupt, NULL))
     {
@@ -266,7 +266,7 @@ static ssize_t stm32l4_rngread(struct file *filep, char *buffer, size_t buflen)
        * enabled.
        */
 
-      sem_init(&g_rngdev.rd_readsem, 0, 0);
+      nxsem_init(&g_rngdev.rd_readsem, 0, 0);
       sem_setprotocol(&g_rngdev.rd_readsem, SEM_PRIO_NONE);
 
       g_rngdev.rd_buflen = buflen;
diff --git a/arch/arm/src/stm32l4/stm32l4_rtc_lowerhalf.c b/arch/arm/src/stm32l4/stm32l4_rtc_lowerhalf.c
index 1abb96583e..2e14ff6719 100644
--- a/arch/arm/src/stm32l4/stm32l4_rtc_lowerhalf.c
+++ b/arch/arm/src/stm32l4/stm32l4_rtc_lowerhalf.c
@@ -573,7 +573,7 @@ static int stm32l4_rdalarm(FAR struct rtc_lowerhalf_s *lower,
 
 FAR struct rtc_lowerhalf_s *stm32l4_rtc_lowerhalf(void)
 {
-  sem_init(&g_rtc_lowerhalf.devsem, 0, 1);
+  nxsem_init(&g_rtc_lowerhalf.devsem, 0, 1);
 
   return (FAR struct rtc_lowerhalf_s *)&g_rtc_lowerhalf;
 }
diff --git a/arch/arm/src/stm32l4/stm32l4_sai.c b/arch/arm/src/stm32l4/stm32l4_sai.c
index f57f2ee593..126ded3028 100644
--- a/arch/arm/src/stm32l4/stm32l4_sai.c
+++ b/arch/arm/src/stm32l4/stm32l4_sai.c
@@ -1274,7 +1274,7 @@ static void sai_buf_initialize(struct stm32l4_sai_s *priv)
   int i;
 
   priv->freelist = NULL;
-  sem_init(&priv->bufsem, 0, CONFIG_STM32L4_SAI_MAXINFLIGHT);
+  nxsem_init(&priv->bufsem, 0, CONFIG_STM32L4_SAI_MAXINFLIGHT);
 
   for (i = 0; i < CONFIG_STM32L4_SAI_MAXINFLIGHT; i++)
     {
@@ -1300,7 +1300,7 @@ static void sai_portinitialize(struct stm32l4_sai_s *priv)
 {
   sai_dump_regs(priv, "Before initialization");
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Create a watchdog timer to catch transfer timeouts */
 
diff --git a/arch/arm/src/stm32l4/stm32l4_sdmmc.c b/arch/arm/src/stm32l4/stm32l4_sdmmc.c
index 4b866db736..b1dfc08fb2 100644
--- a/arch/arm/src/stm32l4/stm32l4_sdmmc.c
+++ b/arch/arm/src/stm32l4/stm32l4_sdmmc.c
@@ -3187,7 +3187,7 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   /* Initialize the SDIO slot structure */
   /* Initialize semaphores */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/stm32l4/stm32l4_spi.c b/arch/arm/src/stm32l4/stm32l4_spi.c
index 856de17230..526582c13f 100644
--- a/arch/arm/src/stm32l4/stm32l4_spi.c
+++ b/arch/arm/src/stm32l4/stm32l4_spi.c
@@ -1510,13 +1510,13 @@ static void spi_bus_initialize(FAR struct stm32l4_spidev_s *priv)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_STM32L4_SPI_DMA
   /* Initialize the SPI semaphores that is used to wait for DMA completion */
 
-  sem_init(&priv->rxsem, 0, 0);
-  sem_init(&priv->txsem, 0, 0);
+  nxsem_init(&priv->rxsem, 0, 0);
+  nxsem_init(&priv->txsem, 0, 0);
 
   /* These semaphores are used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/arm/src/stm32l4/stm32l4x6xx_dma.c b/arch/arm/src/stm32l4/stm32l4x6xx_dma.c
index e63c73be4f..f0660aa5f6 100644
--- a/arch/arm/src/stm32l4/stm32l4x6xx_dma.c
+++ b/arch/arm/src/stm32l4/stm32l4x6xx_dma.c
@@ -347,7 +347,7 @@ void weak_function up_dmainitialize(void)
   for (chndx = 0; chndx < DMA_NCHANNELS; chndx++)
     {
       dmach = &g_dma[chndx];
-      sem_init(&dmach->sem, 0, 1);
+      nxsem_init(&dmach->sem, 0, 1);
 
       /* Attach DMA interrupt vectors */
 
diff --git a/arch/arm/src/tiva/tiva_adclow.c b/arch/arm/src/tiva/tiva_adclow.c
index 46943a07ba..f8481d1920 100644
--- a/arch/arm/src/tiva/tiva_adclow.c
+++ b/arch/arm/src/tiva/tiva_adclow.c
@@ -802,7 +802,7 @@ static struct tiva_adc_s *tiva_adc_struct_init(struct tiva_adc_cfg_s *cfg)
                     {
                       sse->adc = cfg->adc;
                       sse->num = s;
-                      sem_init(&sse->exclsem, SEM_PROCESS_PRIVATE, 1);
+                      nxsem_init(&sse->exclsem, SEM_PROCESS_PRIVATE, 1);
                       sse->ena = false;
                       sse->cfg = true;
                     }
diff --git a/arch/arm/src/tiva/tiva_i2c.c b/arch/arm/src/tiva/tiva_i2c.c
index 6cc2d5fbe1..22345b378c 100644
--- a/arch/arm/src/tiva/tiva_i2c.c
+++ b/arch/arm/src/tiva/tiva_i2c.c
@@ -851,14 +851,14 @@ static inline void tiva_i2c_sem_post(struct tiva_i2c_priv_s *priv)
 
 static inline void tiva_i2c_sem_init(struct tiva_i2c_priv_s *priv)
 {
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifndef CONFIG_I2C_POLLED
   /* This semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
 }
diff --git a/arch/arm/src/tiva/tiva_ssi.c b/arch/arm/src/tiva/tiva_ssi.c
index 9930c6184f..b264d8d240 100644
--- a/arch/arm/src/tiva/tiva_ssi.c
+++ b/arch/arm/src/tiva/tiva_ssi.c
@@ -1640,10 +1640,10 @@ FAR struct spi_dev_s *tiva_ssibus_initialize(int port)
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->xfrsem, 0, 0);
+  nxsem_init(&priv->xfrsem, 0, 0);
   sem_setprotocol(&priv->xfrsem, SEM_PRIO_NONE);
 #endif
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Set all CR1 fields to reset state.  This will be master mode. */
 
diff --git a/arch/avr/src/avr/up_spi.c b/arch/avr/src/avr/up_spi.c
index bf6eda418e..d24d3b12cc 100644
--- a/arch/avr/src/avr/up_spi.c
+++ b/arch/avr/src/avr/up_spi.c
@@ -492,7 +492,7 @@ FAR struct spi_dev_s *avr_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   leave_critical_section(flags);
   return &priv->spidev;
diff --git a/arch/mips/src/pic32mx/pic32mx-spi.c b/arch/mips/src/pic32mx/pic32mx-spi.c
index 1cfd0164d5..cccd98cdbe 100644
--- a/arch/mips/src/pic32mx/pic32mx-spi.c
+++ b/arch/mips/src/pic32mx/pic32mx-spi.c
@@ -948,7 +948,7 @@ FAR struct spi_dev_s *pic32mx_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_PIC32MX_SPI_INTERRUPTS
   /* Enable interrupts at the SPI controller */
diff --git a/arch/mips/src/pic32mz/pic32mz-spi.c b/arch/mips/src/pic32mz/pic32mz-spi.c
index ff56c7f527..b0d8c36632 100644
--- a/arch/mips/src/pic32mz/pic32mz-spi.c
+++ b/arch/mips/src/pic32mz/pic32mz-spi.c
@@ -1349,7 +1349,7 @@ FAR struct spi_dev_s *pic32mz_spibus_initialize(int port)
 
   /* Initialize the SPI semaphore that enforces mutually exclusive access */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
 #ifdef CONFIG_PIC32MZ_SPI_INTERRUPTS
   /* Enable interrupts at the SPI controller */
diff --git a/arch/sim/src/up_touchscreen.c b/arch/sim/src/up_touchscreen.c
index b8b864c89b..9a63017e41 100644
--- a/arch/sim/src/up_touchscreen.c
+++ b/arch/sim/src/up_touchscreen.c
@@ -657,8 +657,8 @@ int sim_tsc_initialize(int minor)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
 
   /* The waitsem semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/arch/sim/src/up_uartwait.c b/arch/sim/src/up_uartwait.c
index 681e87dcdd..5e35e22faa 100644
--- a/arch/sim/src/up_uartwait.c
+++ b/arch/sim/src/up_uartwait.c
@@ -63,7 +63,7 @@ void simuart_initialize(void)
    * have priority inheritance enabled.
    */
 
-  sem_init(&g_uartavail, 0, 0);
+  nxsem_init(&g_uartavail, 0, 0);
   sem_setprotocol(&g_uartavail, SEM_PRIO_NONE);
 }
 
diff --git a/arch/z16/src/z16f/z16f_espi.c b/arch/z16/src/z16f/z16f_espi.c
index 312b2276e4..d8ec62f78d 100644
--- a/arch/z16/src/z16f/z16f_espi.c
+++ b/arch/z16/src/z16f/z16f_espi.c
@@ -809,7 +809,7 @@ FAR struct spi_dev_s *z16_spibus_initialize(int port)
 
       flags = enter_critical_section();
       priv->spi.ops = &g_epsiops;
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 
       /* Set up the SPI pin configuration (board-specific logic is required to
        * configure and manage all chip selects).
diff --git a/arch/z80/src/ez80/ez80_i2c.c b/arch/z80/src/ez80/ez80_i2c.c
index 0e4bdb1b28..0205b0ea03 100644
--- a/arch/z80/src/ez80/ez80_i2c.c
+++ b/arch/z80/src/ez80/ez80_i2c.c
@@ -948,7 +948,7 @@ FAR struct i2c_master_s *ez80_i2cbus_initialize(int port)
 
       /* This semaphore enforces serialized access for I2C transfers */
 
-      sem_init(&g_i2csem, 0, 1);
+      nxsem_init(&g_i2csem, 0, 1);
 
       /* Enable I2C -- but not interrupts */
 
diff --git a/arch/z80/src/z8/z8_i2c.c b/arch/z80/src/z8/z8_i2c.c
index e8c2a0e046..3ac3ca77da 100644
--- a/arch/z80/src/z8/z8_i2c.c
+++ b/arch/z80/src/z8/z8_i2c.c
@@ -661,7 +661,7 @@ FAR struct i2c_master_s *z8_i2cbus_initialize(int port)
 
       /* This semaphore enforces serialized access for I2C transfers */
 
-      sem_init(&g_i2csem, 0, 1);
+      nxsem_init(&g_i2csem, 0, 1);
 
       /* Enable I2C -- no interrupts */
 
diff --git a/audio/audio.c b/audio/audio.c
index b8194908ab..f5b7ee52a2 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -891,7 +891,7 @@ int audio_register(FAR const char *name, FAR struct audio_lowerhalf_s *dev)
 
   /* Initialize the Audio device structure (it was already zeroed by kmm_zalloc()) */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
   upper->dev = dev;
 
 #ifdef CONFIG_AUDIO_CUSTOM_DEV_PATH
diff --git a/binfmt/libbuiltin/libbuiltin_getname.c b/binfmt/libbuiltin/libbuiltin_getname.c
index d1e3958b32..8ca6c24452 100644
--- a/binfmt/libbuiltin/libbuiltin_getname.c
+++ b/binfmt/libbuiltin/libbuiltin_getname.c
@@ -48,26 +48,6 @@
 
 #include <nuttx/binfmt/builtin.h>
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Types
- ****************************************************************************/
-
-/****************************************************************************
- * Private Function Prototypes
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
diff --git a/binfmt/libbuiltin/libbuiltin_isavail.c b/binfmt/libbuiltin/libbuiltin_isavail.c
index 7a480c0f3b..8deefa63e9 100644
--- a/binfmt/libbuiltin/libbuiltin_isavail.c
+++ b/binfmt/libbuiltin/libbuiltin_isavail.c
@@ -52,26 +52,6 @@
 
 #include <nuttx/binfmt/builtin.h>
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Types
- ****************************************************************************/
-
-/****************************************************************************
- * Private Function Prototypes
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
diff --git a/binfmt/pcode.c b/binfmt/pcode.c
index 700d9d3deb..05459c22fb 100644
--- a/binfmt/pcode.c
+++ b/binfmt/pcode.c
@@ -541,7 +541,7 @@ int pcode_initialize(void)
 
   /* Initialize globals */
 
-  sem_init(&g_pcode_handoff.exclsem, 0, 1);
+  nxsem_init(&g_pcode_handoff.exclsem, 0, 1);
 
   /* Mount the test file system */
 
diff --git a/configs/mikroe-stm32f4/src/stm32_touchscreen.c b/configs/mikroe-stm32f4/src/stm32_touchscreen.c
index ea863e8f3d..7420ee07eb 100644
--- a/configs/mikroe-stm32f4/src/stm32_touchscreen.c
+++ b/configs/mikroe-stm32f4/src/stm32_touchscreen.c
@@ -1541,8 +1541,8 @@ int board_tsc_setup(int minor)
   /* Initialize the touchscreen device driver instance */
 
   memset(priv, 0, sizeof(struct tc_dev_s));
-  sem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
 
   /* Register the device as an input device */
 
diff --git a/configs/pic32mx7mmb/src/pic32_touchscreen.c b/configs/pic32mx7mmb/src/pic32_touchscreen.c
index 95b51479e7..56847448d5 100644
--- a/configs/pic32mx7mmb/src/pic32_touchscreen.c
+++ b/configs/pic32mx7mmb/src/pic32_touchscreen.c
@@ -1397,8 +1397,8 @@ int board_tsc_setup(int minor)
   /* Initialize the touchscreen device driver instance */
 
   memset(priv, 0, sizeof(struct tc_dev_s));
-  sem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
 
   /* Register the device as an input device */
 
diff --git a/configs/samv71-xult/src/sam_ili9488.c b/configs/samv71-xult/src/sam_ili9488.c
index 313dcac419..c19674081a 100644
--- a/configs/samv71-xult/src/sam_ili9488.c
+++ b/configs/samv71-xult/src/sam_ili9488.c
@@ -1545,7 +1545,7 @@ int board_lcd_initialize(void)
 
   /* Initialize the LCD state structure */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
 
   /* Allocate a DMA channel */
 
diff --git a/configs/stm32butterfly2/src/stm32_mmcsd.c b/configs/stm32butterfly2/src/stm32_mmcsd.c
index a244a5b5ff..4f2b9a7fcd 100644
--- a/configs/stm32butterfly2/src/stm32_mmcsd.c
+++ b/configs/stm32butterfly2/src/stm32_mmcsd.c
@@ -198,7 +198,7 @@ int stm32_mmcsd_initialize(int minor)
 
   (void)stm32_gpiosetevent(GPIO_SD_CD, true, true, true, stm32_cd, NULL);
 
-  sem_init(&g_cdsem, 0, 0);
+  nxsem_init(&g_cdsem, 0, 0);
   pthread_attr_init(&pattr);
 
 #ifdef CONFIG_DEBUG_FS
diff --git a/crypto/random_pool.c b/crypto/random_pool.c
index f6a53d7119..6c6070bf28 100644
--- a/crypto/random_pool.c
+++ b/crypto/random_pool.c
@@ -370,7 +370,7 @@ static void rng_init(void)
   cryptinfo("Initializing RNG\n");
 
   memset(&g_rng, 0, sizeof(struct rng_s));
-  sem_init(&g_rng.rd_sem, 0, 1);
+  nxsem_init(&g_rng.rd_sem, 0, 1);
 
   /* We do not initialize output here because this is called
    * quite early in boot and there may not be enough entropy.
diff --git a/drivers/analog/adc.c b/drivers/analog/adc.c
index 1fbc580558..c57e9d6f82 100644
--- a/drivers/analog/adc.c
+++ b/drivers/analog/adc.c
@@ -620,8 +620,8 @@ int adc_register(FAR const char *path, FAR struct adc_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->ad_recv.af_sem, 0, 0);
-  sem_init(&dev->ad_closesem, 0, 1);
+  nxsem_init(&dev->ad_recv.af_sem, 0, 0);
+  nxsem_init(&dev->ad_closesem, 0, 1);
 
   /* The receive semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/drivers/analog/comp.c b/drivers/analog/comp.c
index 3dc9b48c3a..a9d24f66ad 100644
--- a/drivers/analog/comp.c
+++ b/drivers/analog/comp.c
@@ -436,10 +436,10 @@ int comp_register(FAR const char *path, FAR struct comp_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->ad_sem, 0, 1);
+  nxsem_init(&dev->ad_sem, 0, 1);
   (void)sem_setprotocol(&dev->ad_sem, SEM_PRIO_NONE);
 
-  sem_init(&dev->ad_readsem, 0, 0);
+  nxsem_init(&dev->ad_readsem, 0, 0);
   (void)sem_setprotocol(&dev->ad_readsem, SEM_PRIO_NONE);
 
   /* Bind the upper-half callbacks to the lower half COMP driver */
diff --git a/drivers/analog/dac.c b/drivers/analog/dac.c
index 131b7e800f..a743170b1e 100644
--- a/drivers/analog/dac.c
+++ b/drivers/analog/dac.c
@@ -499,7 +499,7 @@ int dac_txdone(FAR struct dac_dev_s *dev)
         {
           /* Inform any waiting threads that new xmit space is available */
 
-          ret = sem_getvalue(&dev->ad_xmit.af_sem, &sval);
+          ret = nxsem_getvalue(&dev->ad_xmit.af_sem, &sval);
           if (ret == OK && sval <= 0)
             {
               ret = sem_post(&dev->ad_xmit.af_sem);
@@ -518,8 +518,8 @@ int dac_register(FAR const char *path, FAR struct dac_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->ad_xmit.af_sem, 0, 0);
-  sem_init(&dev->ad_closesem, 0, 1);
+  nxsem_init(&dev->ad_xmit.af_sem, 0, 0);
+  nxsem_init(&dev->ad_closesem, 0, 1);
 
   /* The transmit semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
diff --git a/drivers/analog/ltc1867l.c b/drivers/analog/ltc1867l.c
index 0f5bf1a758..36236a9791 100644
--- a/drivers/analog/ltc1867l.c
+++ b/drivers/analog/ltc1867l.c
@@ -237,7 +237,7 @@ static int adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
   int32_t dataToPost;
   int ret = OK;
 
-  if(cmd == ANIOC_TRIGGER)
+  if (cmd == ANIOC_TRIGGER)
     {
       while (sem_wait(&priv->sem) != OK);
 
@@ -344,11 +344,11 @@ int ltc1867l_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
   adcpriv->channel_config = channel_config;
   adcpriv->channel_config_count = channel_config_count;
 
-  ret = sem_init(&adcpriv->sem, 1, 1);
-  if(ret == -1)
+  ret = nxsem_init(&adcpriv->sem, 1, 1);
+  if (ret < 0)
     {
       kmm_free(adcpriv);
-      return -errno;
+      return ret;
     }
 
   adcdev = (FAR struct adc_dev_s *)kmm_malloc(sizeof(struct adc_dev_s));
diff --git a/drivers/analog/opamp.c b/drivers/analog/opamp.c
index 666b19a8ce..fc18e35d82 100644
--- a/drivers/analog/opamp.c
+++ b/drivers/analog/opamp.c
@@ -229,7 +229,7 @@ int opamp_register(FAR const char *path, FAR struct opamp_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->ad_closesem, 0, 1);
+  nxsem_init(&dev->ad_closesem, 0, 1);
 
   /* Register the OPAMP character driver */
 
diff --git a/drivers/audio/cs43l22.c b/drivers/audio/cs43l22.c
index 239144c6da..263d2109f2 100644
--- a/drivers/audio/cs43l22.c
+++ b/drivers/audio/cs43l22.c
@@ -1920,7 +1920,7 @@ FAR struct audio_lowerhalf_s *cs43l22_initialize(FAR struct i2c_master_s *i2c,
       priv->i2c        = i2c;
       priv->i2s        = i2s;
 
-      sem_init(&priv->pendsem, 0, 1);
+      nxsem_init(&priv->pendsem, 0, 1);
       dq_init(&priv->pendq);
       dq_init(&priv->doneq);
 
diff --git a/drivers/audio/i2schar.c b/drivers/audio/i2schar.c
index 2701a67dc2..3b6d2aed5c 100644
--- a/drivers/audio/i2schar.c
+++ b/drivers/audio/i2schar.c
@@ -393,7 +393,7 @@ int i2schar_register(FAR struct i2s_dev_s *i2s, int minor)
       /* Initialize the I2S character device structure */
 
       priv->i2s = i2s;
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 
       /* Create the character device name */
 
diff --git a/drivers/audio/tone.c b/drivers/audio/tone.c
index f9b5393f73..2d003da22e 100644
--- a/drivers/audio/tone.c
+++ b/drivers/audio/tone.c
@@ -962,7 +962,7 @@ int tone_register(FAR const char *path, FAR struct pwm_lowerhalf_s *tone,
    * kmm_zalloc()).
    */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
   upper->devtone = tone;
   upper->oneshot = oneshot;
 #ifdef CONFIG_PWM_MULTICHAN
diff --git a/drivers/audio/vs1053.c b/drivers/audio/vs1053.c
index 9c41e9fd78..9656f70406 100644
--- a/drivers/audio/vs1053.c
+++ b/drivers/audio/vs1053.c
@@ -1835,7 +1835,7 @@ struct audio_lowerhalf_s *vs1053_initialize(FAR struct spi_dev_s *spi,
       dev->bass        = 0;
       dev->treble      = 0;
 #endif
-      sem_init(&dev->apbq_sem, 0, 1);
+      nxsem_init(&dev->apbq_sem, 0, 1);
       dq_init(&dev->apbq);
 
       /* Reset the VS1053 chip */
diff --git a/drivers/audio/wm8904.c b/drivers/audio/wm8904.c
index 23da3ce9a9..5b6c552371 100644
--- a/drivers/audio/wm8904.c
+++ b/drivers/audio/wm8904.c
@@ -2508,7 +2508,7 @@ FAR struct audio_lowerhalf_s *
       priv->i2c        = i2c;
       priv->i2s        = i2s;
 
-      sem_init(&priv->pendsem, 0, 1);
+      nxsem_init(&priv->pendsem, 0, 1);
       dq_init(&priv->pendq);
       dq_init(&priv->doneq);
 
diff --git a/drivers/bch/bchlib_setup.c b/drivers/bch/bchlib_setup.c
index be20613fdc..d4a37a49ba 100644
--- a/drivers/bch/bchlib_setup.c
+++ b/drivers/bch/bchlib_setup.c
@@ -118,7 +118,7 @@ int bchlib_setup(const char *blkdev, bool readonly, FAR void **handle)
 
   /* Save the geometry info and complete initialization of the structure */
 
-  sem_init(&bch->sem, 0, 1);
+  nxsem_init(&bch->sem, 0, 1);
   bch->nsectors = geo.geo_nsectors;
   bch->sectsize = geo.geo_sectorsize;
   bch->sector   = (size_t)-1;
diff --git a/drivers/can/can.c b/drivers/can/can.c
index 730d7e84b5..be6b4bc703 100644
--- a/drivers/can/can.c
+++ b/drivers/can/can.c
@@ -1169,11 +1169,11 @@ int can_register(FAR const char *path, FAR struct can_dev_s *dev)
 
   /* Initialize semaphores */
 
-  sem_init(&dev->cd_xmit.tx_sem, 0, 1);
-  sem_init(&dev->cd_recv.rx_sem, 0, 1);
-  sem_init(&dev->cd_closesem,    0, 1);
+  nxsem_init(&dev->cd_xmit.tx_sem, 0, 1);
+  nxsem_init(&dev->cd_recv.rx_sem, 0, 1);
+  nxsem_init(&dev->cd_closesem,    0, 1);
 #ifndef CONFIG_DISABLE_POLL
-  sem_init(&dev->cd_pollsem,     0, 1);
+  nxsem_init(&dev->cd_pollsem,     0, 1);
 #endif
 
   for (i = 0; i < CONFIG_CAN_NPENDINGRTR; i++)
@@ -1182,7 +1182,7 @@ int can_register(FAR const char *path, FAR struct can_dev_s *dev)
        * and should not have priority inheritance enabled.
        */
 
-      sem_init(&dev->cd_rtr[i].cr_sem, 0, 0);
+      nxsem_init(&dev->cd_rtr[i].cr_sem, 0, 0);
       sem_setprotocol(&dev->cd_rtr[i].cr_sem, SEM_PRIO_NONE);
       dev->cd_rtr[i].cr_msg = NULL;
     }
diff --git a/drivers/can/mcp2515.c b/drivers/can/mcp2515.c
index df1092bfaa..f943febb41 100644
--- a/drivers/can/mcp2515.c
+++ b/drivers/can/mcp2515.c
@@ -1144,7 +1144,7 @@ static void mcp2515_reset_lowlevel(FAR struct mcp2515_can_s *priv)
    */
 
   sem_destroy(&priv->txfsem);
-  sem_init(&priv->txfsem, 0, config->ntxbuffers);
+  nxsem_init(&priv->txfsem, 0, config->ntxbuffers);
 
   /* Define the current state and unlock */
 
@@ -2516,8 +2516,8 @@ FAR struct mcp2515_can_s *mcp2515_instantiate(FAR struct mcp2515_config_s *confi
 
   /* Initialize semaphores */
 
-  sem_init(&priv->locksem, 0, 1);
-  sem_init(&priv->txfsem, 0, config->ntxbuffers);
+  nxsem_init(&priv->locksem, 0, 1);
+  nxsem_init(&priv->txfsem, 0, config->ntxbuffers);
 
   /* And put the hardware in the initial state */
 
diff --git a/drivers/eeprom/spi_xx25xx.c b/drivers/eeprom/spi_xx25xx.c
index 5fb5a37fdd..bdbf77310c 100644
--- a/drivers/eeprom/spi_xx25xx.c
+++ b/drivers/eeprom/spi_xx25xx.c
@@ -800,7 +800,7 @@ int ee25xx_initialize(FAR struct spi_dev_s *dev, FAR char *devname,
       return -ENOMEM;
     }
 
-  sem_init(&eedev->sem, 0, 1);
+  nxsem_init(&eedev->sem, 0, 1);
 
   eedev->spi      = dev;
   eedev->size     = 128 << g_ee25xx_devices[devtype].bytes;
diff --git a/drivers/i2c/i2c_driver.c b/drivers/i2c/i2c_driver.c
index 79f3bb98e6..541e696712 100644
--- a/drivers/i2c/i2c_driver.c
+++ b/drivers/i2c/i2c_driver.c
@@ -405,7 +405,7 @@ int i2c_register(FAR struct i2c_master_s *i2c, int bus)
 
       priv->i2c = i2c;
 #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 #endif
 
       /* Create the character device name */
diff --git a/drivers/input/ads7843e.c b/drivers/input/ads7843e.c
index 5b8dc4f542..514aab9d31 100644
--- a/drivers/input/ads7843e.c
+++ b/drivers/input/ads7843e.c
@@ -1190,8 +1190,8 @@ int ads7843e_register(FAR struct spi_dev_s *spi,
 
   /* Initialize semaphores */
 
-  sem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0);    /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0);    /* Initialize pen event wait semaphore */
 
   /* The pen event semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/input/ajoystick.c b/drivers/input/ajoystick.c
index 76c93e43c7..beeced01a6 100644
--- a/drivers/input/ajoystick.c
+++ b/drivers/input/ajoystick.c
@@ -873,7 +873,7 @@ int ajoy_register(FAR const char *devname,
   /* Initialize the new ajoystick driver instance */
 
   priv->au_lower = lower;
-  sem_init(&priv->au_exclsem, 0, 1);
+  nxsem_init(&priv->au_exclsem, 0, 1);
 
   DEBUGASSERT(lower->al_buttons);
   priv->au_sample = lower->al_buttons(lower);
diff --git a/drivers/input/button_upper.c b/drivers/input/button_upper.c
index 816cf01c4a..9db9e2dc4c 100644
--- a/drivers/input/button_upper.c
+++ b/drivers/input/button_upper.c
@@ -855,7 +855,7 @@ int btn_register(FAR const char *devname,
   /* Initialize the new button driver instance */
 
   priv->bu_lower = lower;
-  sem_init(&priv->bu_exclsem, 0, 1);
+  nxsem_init(&priv->bu_exclsem, 0, 1);
 
   DEBUGASSERT(lower->bl_buttons);
   priv->bu_sample = lower->bl_buttons(lower);
diff --git a/drivers/input/cypress_mbr3108.c b/drivers/input/cypress_mbr3108.c
index d1b29f672c..a08493cbfe 100644
--- a/drivers/input/cypress_mbr3108.c
+++ b/drivers/input/cypress_mbr3108.c
@@ -1136,7 +1136,7 @@ int cypress_mbr3108_register(FAR const char *devpath,
   priv->board = board_config;
   priv->sensor_conf = sensor_conf;
 
-  sem_init(&priv->devsem, 0, 1);
+  nxsem_init(&priv->devsem, 0, 1);
 
   ret = register_driver(devpath, &g_mbr3108_fileops, 0666, priv);
   if (ret < 0)
diff --git a/drivers/input/djoystick.c b/drivers/input/djoystick.c
index c0559208fb..28cfb55be4 100644
--- a/drivers/input/djoystick.c
+++ b/drivers/input/djoystick.c
@@ -869,7 +869,7 @@ int djoy_register(FAR const char *devname,
   /* Initialize the new djoystick driver instance */
 
   priv->du_lower = lower;
-  sem_init(&priv->du_exclsem, 0, 1);
+  nxsem_init(&priv->du_exclsem, 0, 1);
 
   DEBUGASSERT(lower->dl_sample);
   priv->du_sample = lower->dl_sample(lower);
diff --git a/drivers/input/max11802.c b/drivers/input/max11802.c
index e190b5bc2e..d6ec935869 100644
--- a/drivers/input/max11802.c
+++ b/drivers/input/max11802.c
@@ -1193,8 +1193,8 @@ int max11802_register(FAR struct spi_dev_s *spi,
 
   /* Initialize semaphores */
 
-  sem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0);    /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0);    /* Initialize pen event wait semaphore */
 
   /* The pen event semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/input/mxt.c b/drivers/input/mxt.c
index c7364fa383..65beeb41fb 100644
--- a/drivers/input/mxt.c
+++ b/drivers/input/mxt.c
@@ -1905,8 +1905,8 @@ int mxt_register(FAR struct i2c_master_s *i2c,
 
   /* Initialize semaphores */
 
-  sem_init(&priv->devsem, 0, 1);  /* Initialize device semaphore */
-  sem_init(&priv->waitsem, 0, 0); /* Initialize event wait semaphore */
+  nxsem_init(&priv->devsem, 0, 1);  /* Initialize device semaphore */
+  nxsem_init(&priv->waitsem, 0, 0); /* Initialize event wait semaphore */
 
   /* The event wait semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/input/stmpe811_base.c b/drivers/input/stmpe811_base.c
index 62b86a420f..ecf7ee3257 100644
--- a/drivers/input/stmpe811_base.c
+++ b/drivers/input/stmpe811_base.c
@@ -297,7 +297,7 @@ STMPE811_HANDLE stmpe811_instantiate(FAR struct i2c_master_s *dev,
 
   /* Initialize the device state structure */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->config = config;
 
 #ifdef CONFIG_STMPE811_SPI
diff --git a/drivers/input/tsc2007.c b/drivers/input/tsc2007.c
index fb82cc0557..2141a780eb 100644
--- a/drivers/input/tsc2007.c
+++ b/drivers/input/tsc2007.c
@@ -1255,8 +1255,8 @@ int tsc2007_register(FAR struct i2c_master_s *dev,
   memset(priv, 0, sizeof(struct tsc2007_dev_s));
   priv->i2c    = dev;             /* Save the I2C device handle */
   priv->config = config;          /* Save the board configuration */
-  sem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
-  sem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
+  nxsem_init(&priv->devsem,  0, 1); /* Initialize device structure semaphore */
+  nxsem_init(&priv->waitsem, 0, 0); /* Initialize pen event wait semaphore */
 
   /* Make sure that interrupts are disabled */
 
diff --git a/drivers/ioexpander/pca9555.c b/drivers/ioexpander/pca9555.c
index c250fb6e82..8009566744 100644
--- a/drivers/ioexpander/pca9555.c
+++ b/drivers/ioexpander/pca9555.c
@@ -951,7 +951,7 @@ FAR struct ioexpander_dev_s *pca9555_initialize(FAR struct i2c_master_s *i2cdev,
   pcadev->config->enable(pcadev->config, TRUE);
 #endif
 
-  sem_init(&pcadev->exclsem, 0, 1);
+  nxsem_init(&pcadev->exclsem, 0, 1);
   return &pcadev->dev;
 }
 
diff --git a/drivers/ioexpander/pcf8574.c b/drivers/ioexpander/pcf8574.c
index 4171017c2f..0d85d1a3e2 100644
--- a/drivers/ioexpander/pcf8574.c
+++ b/drivers/ioexpander/pcf8574.c
@@ -1130,7 +1130,7 @@ FAR struct ioexpander_dev_s *pcf8574_initialize(FAR struct i2c_master_s *i2c,
   priv->config->enable(config, true);
 #endif
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->dev;
 }
 
diff --git a/drivers/ioexpander/skeleton.c b/drivers/ioexpander/skeleton.c
index 77e390a2f9..d4ec128e98 100644
--- a/drivers/ioexpander/skeleton.c
+++ b/drivers/ioexpander/skeleton.c
@@ -760,7 +760,7 @@ FAR struct ioexpander_dev_s *skel_initialize(void)
 
 #endif
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->dev;
 }
 
diff --git a/drivers/ioexpander/tca64xx.c b/drivers/ioexpander/tca64xx.c
index c23b428cf2..ff3c827e1f 100644
--- a/drivers/ioexpander/tca64xx.c
+++ b/drivers/ioexpander/tca64xx.c
@@ -1405,7 +1405,7 @@ FAR struct ioexpander_dev_s *tca64_initialize(FAR struct i2c_master_s *i2c,
   priv->config->enable(config, true);
 #endif
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   return &priv->dev;
 }
 
diff --git a/drivers/lcd/pcf8574_lcd_backpack.c b/drivers/lcd/pcf8574_lcd_backpack.c
index 6979539c48..a69deb153f 100644
--- a/drivers/lcd/pcf8574_lcd_backpack.c
+++ b/drivers/lcd/pcf8574_lcd_backpack.c
@@ -1595,7 +1595,7 @@ int pcf8574_lcd_backpack_register(FAR const char *devpath,
   priv->bl_bit = priv->cfg.bl_active_high ? 0 : (1 << priv->cfg.bl);
   priv->refs = 0;
   priv->unlinked = false;
-  sem_init(&priv->sem_excl, 0, 1);
+  nxsem_init(&priv->sem_excl, 0, 1);
 
   /* Initialize */
 
diff --git a/drivers/leds/rgbled.c b/drivers/leds/rgbled.c
index b918f367ff..cb8f86badf 100644
--- a/drivers/leds/rgbled.c
+++ b/drivers/leds/rgbled.c
@@ -454,7 +454,7 @@ int rgbled_register(FAR const char *path, FAR struct pwm_lowerhalf_s *ledr,
    * kmm_zalloc())
    */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
   upper->devledr = ledr;
   upper->devledg = ledg;
   upper->devledb = ledb;
diff --git a/drivers/leds/userled_upper.c b/drivers/leds/userled_upper.c
index dbf8f919c1..76a7948393 100644
--- a/drivers/leds/userled_upper.c
+++ b/drivers/leds/userled_upper.c
@@ -555,7 +555,7 @@ int userled_register(FAR const char *devname,
   /* Initialize the new LED driver instance */
 
   priv->lu_lower = lower;
-  sem_init(&priv->lu_exclsem, 0, 1);
+  nxsem_init(&priv->lu_exclsem, 0, 1);
 
   DEBUGASSERT(lower && lower->ll_supported);
   priv->lu_supported = lower->ll_supported(lower);
diff --git a/drivers/loop/losetup.c b/drivers/loop/losetup.c
index 65d9f9e9cd..b850c3144d 100644
--- a/drivers/loop/losetup.c
+++ b/drivers/loop/losetup.c
@@ -413,7 +413,7 @@ int losetup(FAR const char *devname, FAR const char *filename,
 
   /* Initialize the loop device structure. */
 
-  sem_init(&dev->sem, 0, 1);
+  nxsem_init(&dev->sem, 0, 1);
   dev->nsectors  = (sb.st_size - offset) / sectsize;
   dev->sectsize  = sectsize;
   dev->offset    = offset;
diff --git a/drivers/mmcsd/mmcsd_sdio.c b/drivers/mmcsd/mmcsd_sdio.c
index 1411a6d5f5..7065cf3e7e 100644
--- a/drivers/mmcsd/mmcsd_sdio.c
+++ b/drivers/mmcsd/mmcsd_sdio.c
@@ -3288,7 +3288,7 @@ int mmcsd_slotinitialize(int minor, FAR struct sdio_dev_s *dev)
       /* Initialize the MMC/SD state structure */
 
       memset(priv, 0, sizeof(struct mmcsd_state_s));
-      sem_init(&priv->sem, 0, 1);
+      nxsem_init(&priv->sem, 0, 1);
 
       /* Bind the MMCSD driver to the MMCSD state structure */
 
diff --git a/drivers/mmcsd/mmcsd_spi.c b/drivers/mmcsd/mmcsd_spi.c
index 9a7de84fb3..4e31d21a95 100644
--- a/drivers/mmcsd/mmcsd_spi.c
+++ b/drivers/mmcsd/mmcsd_spi.c
@@ -1933,7 +1933,7 @@ int mmcsd_spislotinitialize(int minor, int slotno, FAR struct spi_dev_s *spi)
 
   slot = &g_mmcsdslot[slotno];
   memset(slot, 0, sizeof(struct mmcsd_slot_s));
-  sem_init(&slot->sem, 0, 1);
+  nxsem_init(&slot->sem, 0, 1);
 
 #ifdef CONFIG_DEBUG_FEATURES
   if (slot->spi)
diff --git a/drivers/mtd/mtd_config.c b/drivers/mtd/mtd_config.c
index 2566efedc8..3021d604a7 100644
--- a/drivers/mtd/mtd_config.c
+++ b/drivers/mtd/mtd_config.c
@@ -1394,7 +1394,7 @@ int mtdconfig_register(FAR struct mtd_dev_s *mtd)
       /* Initialize the mtdconfig device structure */
 
       dev->mtd = mtd;
-      sem_init(&dev->exclsem, 0, 1);
+      nxsem_init(&dev->exclsem, 0, 1);
 
       /* Get the device geometry. (casting to uintptr_t first eliminates
        * complaints on some architectures where the sizeof long is different
diff --git a/drivers/mtd/mtd_nand.c b/drivers/mtd/mtd_nand.c
index b5872e6854..78887a4cb1 100644
--- a/drivers/mtd/mtd_nand.c
+++ b/drivers/mtd/mtd_nand.c
@@ -967,7 +967,7 @@ FAR struct mtd_dev_s *nand_initialize(FAR struct nand_raw_s *raw)
   nand->mtd.ioctl  = nand_ioctl;
   nand->raw        = raw;
 
-  sem_init(&nand->exclsem, 0, 1);
+  nxsem_init(&nand->exclsem, 0, 1);
 
   /* Scan the device for bad blocks */
 
diff --git a/drivers/net/slip.c b/drivers/net/slip.c
index 36eefbef95..9b077b0468 100644
--- a/drivers/net/slip.c
+++ b/drivers/net/slip.c
@@ -956,7 +956,7 @@ int slip_initialize(int intf, FAR const char *devname)
 
   /* Initialize the wait semaphore */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 
   /* Put the interface in the down state.  This usually amounts to resetting
diff --git a/drivers/net/telnet.c b/drivers/net/telnet.c
index 9e16d11328..2913479c7e 100644
--- a/drivers/net/telnet.c
+++ b/drivers/net/telnet.c
@@ -777,7 +777,7 @@ static int telnet_session(FAR struct telnet_session_s *session)
 
   /* Initialize the allocated driver instance */
 
-  sem_init(&priv->td_exclsem, 0, 1);
+  nxsem_init(&priv->td_exclsem, 0, 1);
 
   priv->td_state   = STATE_NORMAL;
   priv->td_crefs   = 0;
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 1bef4351cc..87fccebb35 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -872,8 +872,8 @@ static int tun_dev_init(FAR struct tun_device_s *priv, FAR struct file *filep,
 
   /* Initialize the mutual exlcusion and wait semaphore */
 
-  sem_init(&priv->waitsem, 0, 1);
-  sem_init(&priv->read_wait_sem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 1);
+  nxsem_init(&priv->read_wait_sem, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have
    * priority inheritance enabled.
@@ -1272,7 +1272,7 @@ static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
 
 int tun_initialize(void)
 {
-  sem_init(&g_tun.waitsem, 0, 1);
+  nxsem_init(&g_tun.waitsem, 0, 1);
 
   g_tun.free_tuns = (1 << CONFIG_TUN_NINTERFACES) - 1;
 
diff --git a/drivers/pipes/pipe_common.c b/drivers/pipes/pipe_common.c
index 263058ec25..8eab11ac28 100644
--- a/drivers/pipes/pipe_common.c
+++ b/drivers/pipes/pipe_common.c
@@ -169,9 +169,9 @@ FAR struct pipe_dev_s *pipecommon_allocdev(size_t bufsize)
       /* Initialize the private structure */
 
       memset(dev, 0, sizeof(struct pipe_dev_s));
-      sem_init(&dev->d_bfsem, 0, 1);
-      sem_init(&dev->d_rdsem, 0, 0);
-      sem_init(&dev->d_wrsem, 0, 0);
+      nxsem_init(&dev->d_bfsem, 0, 1);
+      nxsem_init(&dev->d_rdsem, 0, 0);
+      nxsem_init(&dev->d_wrsem, 0, 0);
 
      /* The read/write wait semaphores are used for signaling and, hence,
       * should not have priority inheritance enabled.
@@ -254,7 +254,7 @@ int pipecommon_open(FAR struct file *filep)
 
       if (dev->d_nwriters == 1)
         {
-          while (sem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
+          while (nxsem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
             {
               sem_post(&dev->d_rdsem);
             }
@@ -349,7 +349,7 @@ int pipecommon_close(FAR struct file *filep)
 
           if (--dev->d_nwriters <= 0)
             {
-              while (sem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
+              while (nxsem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
                 {
                   sem_post(&dev->d_rdsem);
                 }
@@ -494,7 +494,7 @@ ssize_t pipecommon_read(FAR struct file *filep, FAR char *buffer, size_t len)
 
   /* Notify all waiting writers that bytes have been removed from the buffer */
 
-  while (sem_getvalue(&dev->d_wrsem, &sval) == 0 && sval < 0)
+  while (nxsem_getvalue(&dev->d_wrsem, &sval) == 0 && sval < 0)
     {
       sem_post(&dev->d_wrsem);
     }
@@ -580,7 +580,7 @@ ssize_t pipecommon_write(FAR struct file *filep, FAR const char *buffer,
             {
               /* Yes.. Notify all of the waiting readers that more data is available */
 
-              while (sem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
+              while (nxsem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
                 {
                   sem_post(&dev->d_rdsem);
                 }
@@ -603,7 +603,7 @@ ssize_t pipecommon_write(FAR struct file *filep, FAR const char *buffer,
             {
               /* Yes.. Notify all of the waiting readers that more data is available */
 
-              while (sem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
+              while (nxsem_getvalue(&dev->d_rdsem, &sval) == 0 && sval < 0)
                 {
                   sem_post(&dev->d_rdsem);
                 }
diff --git a/drivers/power/bq2425x.c b/drivers/power/bq2425x.c
index 7e6e7dbd72..a93116b46f 100644
--- a/drivers/power/bq2425x.c
+++ b/drivers/power/bq2425x.c
@@ -787,7 +787,7 @@ FAR struct battery_charger_dev_s *
     {
       /* Initialize the BQ2425x device structure */
 
-      sem_init(&priv->batsem, 0, 1);
+      nxsem_init(&priv->batsem, 0, 1);
       priv->ops       = &g_bq2425xops;
       priv->i2c       = i2c;
       priv->addr      = addr;
diff --git a/drivers/power/bq2429x.c b/drivers/power/bq2429x.c
index 675a6eccd7..7aa91eab8e 100644
--- a/drivers/power/bq2429x.c
+++ b/drivers/power/bq2429x.c
@@ -1209,7 +1209,7 @@ FAR struct battery_charger_dev_s *
     {
       /* Initialize the BQ2429x device structure */
 
-      sem_init(&priv->batsem, 0, 1);
+      nxsem_init(&priv->batsem, 0, 1);
       priv->ops       = &g_bq2429xops;
       priv->i2c       = i2c;
       priv->addr      = addr;
diff --git a/drivers/power/max1704x.c b/drivers/power/max1704x.c
index 00f98fc189..6fde917a53 100644
--- a/drivers/power/max1704x.c
+++ b/drivers/power/max1704x.c
@@ -542,7 +542,7 @@ FAR struct battery_gauge_dev_s *max1704x_initialize(FAR struct i2c_master_s *i2c
     {
       /* Initialize the MAX1704x device structure */
 
-      sem_init(&priv->batsem, 0, 1);
+      nxsem_init(&priv->batsem, 0, 1);
       priv->ops       = &g_max1704xops;
       priv->i2c       = i2c;
       priv->addr      = addr;
diff --git a/drivers/power/pm_initialize.c b/drivers/power/pm_initialize.c
index 1ac5878861..52518d2f29 100644
--- a/drivers/power/pm_initialize.c
+++ b/drivers/power/pm_initialize.c
@@ -86,7 +86,7 @@ void pm_initialize(void)
    */
 
   sq_init(&g_pmglobals.registry);
-  sem_init(&g_pmglobals.regsem, 0, 1);
+  nxsem_init(&g_pmglobals.regsem, 0, 1);
 }
 
 #endif /* CONFIG_PM */
diff --git a/drivers/power/powerled.c b/drivers/power/powerled.c
index 354221bfde..46375affc5 100644
--- a/drivers/power/powerled.c
+++ b/drivers/power/powerled.c
@@ -425,7 +425,7 @@ int powerled_register(FAR const char *path, FAR struct powerled_dev_s *dev, FAR
 
   /* Initialize semaphores */
 
-  sem_init(&dev->closesem, 0, 1);
+  nxsem_init(&dev->closesem, 0, 1);
 
   /* Connect POWERLED driver with lower level interface */
 
diff --git a/drivers/power/smps.c b/drivers/power/smps.c
index 1fa5e2a103..e9cd30ba6b 100644
--- a/drivers/power/smps.c
+++ b/drivers/power/smps.c
@@ -518,7 +518,7 @@ int smps_register(FAR const char *path, FAR struct smps_dev_s *dev, FAR void *lo
 
   /* Initialize semaphores */
 
-  sem_init(&dev->closesem, 0, 1);
+  nxsem_init(&dev->closesem, 0, 1);
 
   /* Connect SMPS driver with lower level interface */
 
diff --git a/drivers/pwm.c b/drivers/pwm.c
index 24c5ae4105..a5dfe3c7b6 100644
--- a/drivers/pwm.c
+++ b/drivers/pwm.c
@@ -599,9 +599,9 @@ int pwm_register(FAR const char *path, FAR struct pwm_lowerhalf_s *dev)
 
   /* Initialize the PWM device structure (it was already zeroed by kmm_zalloc()) */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
 #ifdef CONFIG_PWM_PULSECOUNT
-  sem_init(&upper->waitsem, 0, 0);
+  nxsem_init(&upper->waitsem, 0, 0);
 
   /* The wait semaphore is used for signaling and, hence, should not have priority
    * inheritance enabled.
diff --git a/drivers/rwbuffer.c b/drivers/rwbuffer.c
index b1f2838042..293794de59 100644
--- a/drivers/rwbuffer.c
+++ b/drivers/rwbuffer.c
@@ -657,7 +657,7 @@ int rwb_initialize(FAR struct rwbuffer_s *rwb)
 
       /* Initialize the write buffer access semaphore */
 
-      sem_init(&rwb->wrsem, 0, 1);
+      nxsem_init(&rwb->wrsem, 0, 1);
 
       /* Initialize write buffer parameters */
 
@@ -688,7 +688,7 @@ int rwb_initialize(FAR struct rwbuffer_s *rwb)
 
       /* Initialize the read-ahead buffer access semaphore */
 
-      sem_init(&rwb->rhsem, 0, 1);
+      nxsem_init(&rwb->rhsem, 0, 1);
 
       /* Initialize read-ahead buffer parameters */
 
diff --git a/drivers/sensors/adxl345_base.c b/drivers/sensors/adxl345_base.c
index 93ebf9cf45..f94398ef9b 100644
--- a/drivers/sensors/adxl345_base.c
+++ b/drivers/sensors/adxl345_base.c
@@ -407,7 +407,7 @@ ADXL345_HANDLE adxl345_instantiate(FAR struct i2c_master_s *dev,
 
   /* Initialize the device state structure */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->config = config;
 
 #ifdef CONFIG_ADXL345_SPI
diff --git a/drivers/sensors/bmg160.c b/drivers/sensors/bmg160.c
index a8d95094ad..77209253cd 100644
--- a/drivers/sensors/bmg160.c
+++ b/drivers/sensors/bmg160.c
@@ -560,7 +560,7 @@ int bmg160_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
 
   /* Initialize sensor data access semaphore */
 
-  sem_init(&priv->datasem, 0, 1);
+  nxsem_init(&priv->datasem, 0, 1);
 
   /* Setup SPI frequency and mode */
 
diff --git a/drivers/sensors/hc_sr04.c b/drivers/sensors/hc_sr04.c
index 297795a4d1..cae43b57d1 100644
--- a/drivers/sensors/hc_sr04.c
+++ b/drivers/sensors/hc_sr04.c
@@ -121,7 +121,7 @@ static int hcsr04_read_distance(FAR struct hcsr04_dev_s *priv)
 {
   int done;
 
-  sem_getvalue(&priv->conv_donesem, &done);
+  nxsem_getvalue(&priv->conv_donesem, &done);
 
   if (done == 0)
     {
@@ -273,7 +273,7 @@ static bool hcsr04_sample(FAR struct hcsr04_dev_s *priv)
 {
   int done;
 
-  sem_getvalue(&priv->conv_donesem, &done);
+  nxsem_getvalue(&priv->conv_donesem, &done);
 
   return (done == 0);
 }
@@ -446,8 +446,8 @@ int hcsr04_register(FAR const char *devpath,
     }
 
   priv->config = config;
-  sem_init(&priv->devsem, 0, 1);
-  sem_init(&priv->conv_donesem, 0, 0);
+  nxsem_init(&priv->devsem, 0, 1);
+  nxsem_init(&priv->conv_donesem, 0, 0);
 
   ret = register_driver(devpath, &g_hcsr04ops, 0666, priv);
   if (ret < 0)
diff --git a/drivers/sensors/hts221.c b/drivers/sensors/hts221.c
index e2a08147c5..0e466f5a93 100644
--- a/drivers/sensors/hts221.c
+++ b/drivers/sensors/hts221.c
@@ -1105,7 +1105,7 @@ int hts221_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
   priv->addr   = addr;
   priv->i2c    = i2c;
   priv->config = config;
-  sem_init(&priv->devsem, 0, 1);
+  nxsem_init(&priv->devsem, 0, 1);
 
   ret = hts221_load_calibration_data(priv);
   if (ret < 0)
diff --git a/drivers/sensors/kxtj9.c b/drivers/sensors/kxtj9.c
index 365c3dbb48..e58f42e8f9 100644
--- a/drivers/sensors/kxtj9.c
+++ b/drivers/sensors/kxtj9.c
@@ -670,7 +670,7 @@ int kxtj9_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
 
   priv->i2c     = i2c;
   priv->address = address;
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Register the character driver */
 
diff --git a/drivers/sensors/l3gd20.c b/drivers/sensors/l3gd20.c
index 10bcbeb77a..91f2d56141 100644
--- a/drivers/sensors/l3gd20.c
+++ b/drivers/sensors/l3gd20.c
@@ -617,7 +617,7 @@ int l3gd20_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
 
   /* Initialize sensor data access semaphore */
 
-  sem_init(&priv->datasem, 0, 1);
+  nxsem_init(&priv->datasem, 0, 1);
 
   /* Setup SPI frequency and mode */
 
diff --git a/drivers/sensors/lis2dh.c b/drivers/sensors/lis2dh.c
index db6af58e4b..1bf4173398 100644
--- a/drivers/sensors/lis2dh.c
+++ b/drivers/sensors/lis2dh.c
@@ -2015,7 +2015,7 @@ int lis2dh_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
       return -ENOMEM;
     }
 
-  sem_init(&priv->devsem, 0, 1);
+  nxsem_init(&priv->devsem, 0, 1);
 
   priv->fifo_used = false;
 #ifdef LIS2DH_COUNT_INTS
diff --git a/drivers/sensors/lis3dsh.c b/drivers/sensors/lis3dsh.c
index 8e8ed4885c..c455327c9c 100644
--- a/drivers/sensors/lis3dsh.c
+++ b/drivers/sensors/lis3dsh.c
@@ -560,7 +560,7 @@ int lis3dsh_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
   priv->config      = config;
   priv->work.worker = NULL;
 
-  sem_init(&priv->datasem, 0, 1);       /* Initialize sensor data access
+  nxsem_init(&priv->datasem, 0, 1);     /* Initialize sensor data access
                                          * semaphore */
 
   /* Setup SPI frequency and mode */
diff --git a/drivers/sensors/lis3mdl.c b/drivers/sensors/lis3mdl.c
index 18c0e21f8b..4dda4d979f 100644
--- a/drivers/sensors/lis3mdl.c
+++ b/drivers/sensors/lis3mdl.c
@@ -600,7 +600,7 @@ int lis3mdl_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
 
   priv->work.worker = NULL;
 
-  sem_init(&priv->datasem, 0, 1);       /* Initialize sensor data access
+  nxsem_init(&priv->datasem, 0, 1);     /* Initialize sensor data access
                                          * semaphore */
 
   /* Setup SPI frequency and mode */
diff --git a/drivers/sensors/lps25h.c b/drivers/sensors/lps25h.c
index 1eb762af0a..afcc4954fc 100644
--- a/drivers/sensors/lps25h.c
+++ b/drivers/sensors/lps25h.c
@@ -771,8 +771,8 @@ int lps25h_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
       return -ENOMEM;
     }
 
-  sem_init(&dev->devsem, 0, 1);
-  sem_init(&dev->waitsem, 0, 0);
+  nxsem_init(&dev->devsem, 0, 1);
+  nxsem_init(&dev->waitsem, 0, 0);
 
   dev->addr = addr;
   dev->i2c = i2c;
diff --git a/drivers/sensors/mlx90393.c b/drivers/sensors/mlx90393.c
index f50d657527..5db0801d98 100644
--- a/drivers/sensors/mlx90393.c
+++ b/drivers/sensors/mlx90393.c
@@ -589,7 +589,7 @@ int mlx90393_register(FAR const char *devpath, FAR struct spi_dev_s *spi,
 
   priv->work.worker = NULL;
 
-  sem_init(&priv->datasem, 0, 1);       /* Initialize sensor data access
+  nxsem_init(&priv->datasem, 0, 1);     /* Initialize sensor data access
                                          * semaphore */
 
   /* Setup SPI frequency and mode */
diff --git a/drivers/sensors/qencoder.c b/drivers/sensors/qencoder.c
index 894581664f..6f1871d249 100644
--- a/drivers/sensors/qencoder.c
+++ b/drivers/sensors/qencoder.c
@@ -376,7 +376,7 @@ int qe_register(FAR const char *devpath, FAR struct qe_lowerhalf_s *lower)
 
   /* Initialize the PWM device structure (it was already zeroed by kmm_zalloc()) */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
   upper->lower = lower;
 
   /* Register the PWM device */
diff --git a/drivers/sensors/xen1210.c b/drivers/sensors/xen1210.c
index bb7858ae39..b8bb660ceb 100644
--- a/drivers/sensors/xen1210.c
+++ b/drivers/sensors/xen1210.c
@@ -301,7 +301,7 @@ XEN1210_HANDLE xen1210_instantiate(FAR struct spi_dev_s *dev,
 
   /* Initialize the device state structure */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
   priv->config = config;
 
   priv->spi = dev;
diff --git a/drivers/sensors/zerocross.c b/drivers/sensors/zerocross.c
index 770ca55690..7a3460ce71 100644
--- a/drivers/sensors/zerocross.c
+++ b/drivers/sensors/zerocross.c
@@ -526,7 +526,7 @@ int zc_register(FAR const char *devname, FAR struct zc_lowerhalf_s *lower)
   /* Initialize the new zero cross driver instance */
 
   priv->lower = lower;
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* And register the zero cross driver */
 
diff --git a/drivers/serial/ptmx.c b/drivers/serial/ptmx.c
index 6a8a3359ce..4ea9b69c4f 100644
--- a/drivers/serial/ptmx.c
+++ b/drivers/serial/ptmx.c
@@ -310,7 +310,7 @@ int ptmx_register(void)
 {
   /* Initialize driver state */
 
-  sem_init(&g_ptmx.px_exclsem, 0, 1);
+  nxsem_init(&g_ptmx.px_exclsem, 0, 1);
 
   /* Register the PTMX driver */
 
diff --git a/drivers/serial/pty.c b/drivers/serial/pty.c
index 4c27cd89bb..c145a2988a 100644
--- a/drivers/serial/pty.c
+++ b/drivers/serial/pty.c
@@ -777,7 +777,7 @@ static int pty_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
 
                do
                  {
-                   DEBUGVERIFY(sem_getvalue(&devpair->pp_slavesem, &sval));
+                   DEBUGVERIFY(nxsem_getvalue(&devpair->pp_slavesem, &sval));
                    if (sval < 0)
                      {
                        sem_post(&devpair->pp_slavesem);
@@ -1019,8 +1019,8 @@ int pty_register(int minor)
 
   /* Initialize semaphores */
 
-  sem_init(&devpair->pp_slavesem, 0, 0);
-  sem_init(&devpair->pp_exclsem, 0, 1);
+  nxsem_init(&devpair->pp_slavesem, 0, 0);
+  nxsem_init(&devpair->pp_exclsem, 0, 1);
 
   /* The pp_slavesem semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index 0852789630..923397b97f 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -650,12 +650,12 @@ static int uart_close(FAR struct file *filep)
    * a thread currently blocking on any of them.
    */
 
-  sem_reset(&dev->xmitsem,  0);
-  sem_reset(&dev->recvsem,  0);
-  sem_reset(&dev->xmit.sem, 1);
-  sem_reset(&dev->recv.sem, 1);
+  nxsem_reset(&dev->xmitsem,  0);
+  nxsem_reset(&dev->recvsem,  0);
+  nxsem_reset(&dev->xmit.sem, 1);
+  nxsem_reset(&dev->recv.sem, 1);
 #ifndef CONFIG_DISABLE_POLL
-  sem_reset(&dev->pollsem,  1);
+  nxsem_reset(&dev->pollsem,  1);
 #endif
 
   uart_givesem(&dev->closesem);
@@ -1532,13 +1532,13 @@ int uart_register(FAR const char *path, FAR uart_dev_t *dev)
 {
   /* Initialize semaphores */
 
-  sem_init(&dev->xmit.sem, 0, 1);
-  sem_init(&dev->recv.sem, 0, 1);
-  sem_init(&dev->closesem, 0, 1);
-  sem_init(&dev->xmitsem,  0, 0);
-  sem_init(&dev->recvsem,  0, 0);
+  nxsem_init(&dev->xmit.sem, 0, 1);
+  nxsem_init(&dev->recv.sem, 0, 1);
+  nxsem_init(&dev->closesem, 0, 1);
+  nxsem_init(&dev->xmitsem,  0, 0);
+  nxsem_init(&dev->recvsem,  0, 0);
 #ifndef CONFIG_DISABLE_POLL
-  sem_init(&dev->pollsem,  0, 1);
+  nxsem_init(&dev->pollsem,  0, 1);
 #endif
 
   /* The recvsem and xmitsem are used for signaling and, hence, should not have
diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 0e502f6c37..039f37ad09 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -551,7 +551,7 @@ FAR struct spi_dev_s *spi_create_bitbang(FAR const struct spi_bitbang_ops_s *low
   priv->nbits   = 8;
 #endif
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Select an initial state of mode 0, 8-bits, and 400KHz */
 
diff --git a/drivers/spi/spi_driver.c b/drivers/spi/spi_driver.c
index 5f14827c03..a30de61eb4 100644
--- a/drivers/spi/spi_driver.c
+++ b/drivers/spi/spi_driver.c
@@ -384,7 +384,7 @@ int spi_register(FAR struct spi_dev_s *spi, int bus)
 
       priv->spi = spi;
 #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 #endif
 
       /* Create the character device name */
diff --git a/drivers/syslog/ramlog.c b/drivers/syslog/ramlog.c
index b81a7df6a7..5db97388ed 100644
--- a/drivers/syslog/ramlog.c
+++ b/drivers/syslog/ramlog.c
@@ -694,9 +694,9 @@ int ramlog_register(FAR const char *devpath, FAR char *buffer, size_t buflen)
     {
       /* Initialize the non-zero values in the RAM logging device structure */
 
-      sem_init(&priv->rl_exclsem, 0, 1);
+      nxsem_init(&priv->rl_exclsem, 0, 1);
 #ifndef CONFIG_RAMLOG_NONBLOCKING
-      sem_init(&priv->rl_waitsem, 0, 0);
+      nxsem_init(&priv->rl_waitsem, 0, 0);
 
       /* The rl_waitsem semaphore is used for signaling and, hence, should
        * not have priority inheritance enabled.
diff --git a/drivers/syslog/syslog_device.c b/drivers/syslog/syslog_device.c
index a9f4596e78..7247fda48a 100644
--- a/drivers/syslog/syslog_device.c
+++ b/drivers/syslog/syslog_device.c
@@ -405,7 +405,7 @@ int syslog_dev_initialize(FAR const char *devpath, int oflags, int mode)
 
   /* The SYSLOG device is open and ready for writing. */
 
-  sem_init(&g_syslog_dev.sl_sem, 0, 1);
+  nxsem_init(&g_syslog_dev.sl_sem, 0, 1);
   g_syslog_dev.sl_holder = NO_HOLDER;
   g_syslog_dev.sl_state  = SYSLOG_OPENED;
   return OK;
diff --git a/drivers/timers/oneshot.c b/drivers/timers/oneshot.c
index 518071d19d..56556aaa38 100644
--- a/drivers/timers/oneshot.c
+++ b/drivers/timers/oneshot.c
@@ -365,7 +365,7 @@ int oneshot_register(FAR const char *devname,
   /* Initialize the new oneshot timer driver instance */
 
   priv->od_lower = lower;
-  sem_init(&priv->od_exclsem, 0, 1);
+  nxsem_init(&priv->od_exclsem, 0, 1);
 
   /* And register the oneshot timer driver */
 
diff --git a/drivers/timers/watchdog.c b/drivers/timers/watchdog.c
index 7ccab15a06..0d69892799 100644
--- a/drivers/timers/watchdog.c
+++ b/drivers/timers/watchdog.c
@@ -479,7 +479,7 @@ FAR void *watchdog_register(FAR const char *path,
    * by kmm_zalloc()).
    */
 
-  sem_init(&upper->exclsem, 0, 1);
+  nxsem_init(&upper->exclsem, 0, 1);
   upper->lower = lower;
 
   /* Copy the registration path */
diff --git a/drivers/usbdev/usbmsc.c b/drivers/usbdev/usbmsc.c
index d755881918..ba0293017c 100644
--- a/drivers/usbdev/usbmsc.c
+++ b/drivers/usbdev/usbmsc.c
@@ -1358,9 +1358,9 @@ int usbmsc_configure(unsigned int nluns, void **handle)
 
   /* Initialize semaphores */
 
-  sem_init(&priv->thsynch, 0, 0);
-  sem_init(&priv->thlock, 0, 1);
-  sem_init(&priv->thwaitsem, 0, 0);
+  nxsem_init(&priv->thsynch, 0, 0);
+  nxsem_init(&priv->thlock, 0, 1);
+  nxsem_init(&priv->thwaitsem, 0, 0);
 
   /* The thsynch and thwaitsem semaphores are used for signaling and, hence,
    * should not have priority inheritance enabled.
diff --git a/drivers/usbhost/usbhost_cdcacm.c b/drivers/usbhost/usbhost_cdcacm.c
index 4b0a9e5c42..4c719beb66 100644
--- a/drivers/usbhost/usbhost_cdcacm.c
+++ b/drivers/usbhost/usbhost_cdcacm.c
@@ -1901,7 +1901,7 @@ usbhost_create(FAR struct usbhost_hubport_s *hport,
 
           /* Initialize semaphores (this works okay in the interrupt context) */
 
-          sem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->exclsem, 0, 1);
 
           /* Set up the serial lower-half interface */
 
diff --git a/drivers/usbhost/usbhost_devaddr.c b/drivers/usbhost/usbhost_devaddr.c
index 1b51a08926..803e547bac 100644
--- a/drivers/usbhost/usbhost_devaddr.c
+++ b/drivers/usbhost/usbhost_devaddr.c
@@ -254,7 +254,7 @@ void usbhost_devaddr_initialize(FAR struct usbhost_roothubport_s *rhport)
   devgen = &rhport->devgen;
 
   memset(devgen, 0, sizeof(struct usbhost_devaddr_s));
-  sem_init(&devgen->exclsem, 0, 1);
+  nxsem_init(&devgen->exclsem, 0, 1);
   devgen->next = 1;
 }
 
diff --git a/drivers/usbhost/usbhost_hidkbd.c b/drivers/usbhost/usbhost_hidkbd.c
index 6a5be0e9ba..ab79d2b107 100644
--- a/drivers/usbhost/usbhost_hidkbd.c
+++ b/drivers/usbhost/usbhost_hidkbd.c
@@ -1862,8 +1862,8 @@ static FAR struct usbhost_class_s *
 
           /* Initialize semaphores */
 
-          sem_init(&priv->exclsem, 0, 1);
-          sem_init(&priv->waitsem, 0, 0);
+          nxsem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->waitsem, 0, 0);
 
           /* The waitsem semaphore is used for signaling and, hence, should
            * not have priority inheritance enabled.
@@ -2427,8 +2427,8 @@ int usbhost_kbdinit(void)
 {
   /* Perform any one-time initialization of the class implementation */
 
-  sem_init(&g_exclsem, 0, 1);
-  sem_init(&g_syncsem, 0, 0);
+  nxsem_init(&g_exclsem, 0, 1);
+  nxsem_init(&g_syncsem, 0, 0);
 
   /* The g_syncsem semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/usbhost/usbhost_hidmouse.c b/drivers/usbhost/usbhost_hidmouse.c
index dbd0033920..ec04a3ea79 100644
--- a/drivers/usbhost/usbhost_hidmouse.c
+++ b/drivers/usbhost/usbhost_hidmouse.c
@@ -1932,8 +1932,8 @@ static FAR struct usbhost_class_s *
 
           /* Initialize semaphores */
 
-          sem_init(&priv->exclsem, 0, 1);
-          sem_init(&priv->waitsem, 0, 0);
+          nxsem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->waitsem, 0, 0);
 
           /* The waitsem semaphore is used for signaling and, hence, should
            * not have priority inheritance enabled.
@@ -2557,8 +2557,8 @@ int usbhost_mouse_init(void)
 {
   /* Perform any one-time initialization of the class implementation */
 
-  sem_init(&g_exclsem, 0, 1);
-  sem_init(&g_syncsem, 0, 0);
+  nxsem_init(&g_exclsem, 0, 1);
+  nxsem_init(&g_syncsem, 0, 0);
 
   /* The g_syncsem semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/usbhost/usbhost_hub.c b/drivers/usbhost/usbhost_hub.c
index add1455ca3..a3a54ccd07 100644
--- a/drivers/usbhost/usbhost_hub.c
+++ b/drivers/usbhost/usbhost_hub.c
@@ -1302,7 +1302,7 @@ static FAR struct usbhost_class_s *
 
   /* Initialize semaphores (this works okay in the interrupt context) */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Initialize per-port data */
 
diff --git a/drivers/usbhost/usbhost_skeleton.c b/drivers/usbhost/usbhost_skeleton.c
index a03d1101f7..1f89359fdf 100644
--- a/drivers/usbhost/usbhost_skeleton.c
+++ b/drivers/usbhost/usbhost_skeleton.c
@@ -889,7 +889,7 @@ static FAR struct usbhost_class_s *usbhost_create(FAR struct usbhost_hubport_s *
 
           /* Initialize semaphores (this works okay in the interrupt context) */
 
-          sem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->exclsem, 0, 1);
 
           /* Return the instance of the USB class driver */
 
diff --git a/drivers/usbhost/usbhost_storage.c b/drivers/usbhost/usbhost_storage.c
index c7df71a7f4..24bb7bd736 100644
--- a/drivers/usbhost/usbhost_storage.c
+++ b/drivers/usbhost/usbhost_storage.c
@@ -1703,7 +1703,7 @@ usbhost_create(FAR struct usbhost_hubport_s *hport,
 
           /* Initialize semaphores (this works okay in the interrupt context) */
 
-          sem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->exclsem, 0, 1);
 
           /* NOTE: We do not yet know the geometry of the USB mass storage device */
 
diff --git a/drivers/usbhost/usbhost_xboxcontroller.c b/drivers/usbhost/usbhost_xboxcontroller.c
index 6fcf49d6a8..984064087c 100644
--- a/drivers/usbhost/usbhost_xboxcontroller.c
+++ b/drivers/usbhost/usbhost_xboxcontroller.c
@@ -1574,8 +1574,8 @@ static FAR struct usbhost_class_s *usbhost_create(FAR struct usbhost_hubport_s *
 
           /* Initialize semaphores (this works okay in the interrupt context) */
 
-          sem_init(&priv->exclsem, 0, 1);
-          sem_init(&priv->waitsem, 0, 0);
+          nxsem_init(&priv->exclsem, 0, 1);
+          nxsem_init(&priv->waitsem, 0, 0);
 
           /* The waitsem semaphore is used for signaling and, hence, should
            * not have priority inheritance enabled.
@@ -2213,8 +2213,8 @@ int usbhost_xboxcontroller_init(void)
 
   /* Perform any one-time initialization of the class implementation */
 
-  sem_init(&g_exclsem, 0, 1);
-  sem_init(&g_syncsem, 0, 0);
+  nxsem_init(&g_exclsem, 0, 1);
+  nxsem_init(&g_syncsem, 0, 0);
 
   /* The g_syncsem semaphore is used for signaling and, hence, should not
    * have priority inheritance enabled.
diff --git a/drivers/usbmisc/fusb301.c b/drivers/usbmisc/fusb301.c
index c106c0470b..47d0571b9a 100644
--- a/drivers/usbmisc/fusb301.c
+++ b/drivers/usbmisc/fusb301.c
@@ -830,7 +830,7 @@ int fusb301_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
 
   /* Initialize device structure semaphore */
 
-  sem_init(&priv->devsem, 0, 1);
+  nxsem_init(&priv->devsem, 0, 1);
 
   priv->int_pending = false;
   priv->i2c         = i2c;
diff --git a/drivers/wireless/cc3000/cc3000.c b/drivers/wireless/cc3000/cc3000.c
index f290f96789..f4a9fdb24d 100644
--- a/drivers/wireless/cc3000/cc3000.c
+++ b/drivers/wireless/cc3000/cc3000.c
@@ -503,7 +503,7 @@ static void *select_thread_func(FAR void *arg)
                   int count;
                   do
                     {
-                      sem_getvalue(&priv->sockets[s].semwait, &count);
+                      nxsem_getvalue(&priv->sockets[s].semwait, &count);
                       if (count < 0)
                         {
                           /* Release the waiting threads */
@@ -714,7 +714,7 @@ static void *cc3000_worker(FAR void *arg)
                     ninfo("Completed S:%d irq :%d\n",
                           priv->state, priv->config->irq_read(priv->config));
 
-                    sem_getvalue(&priv->irqsem, &count);
+                    nxsem_getvalue(&priv->irqsem, &count);
                     if (priv->config->irq_read(priv->config) && count == 0)
                       {
                         sem_post(&priv->irqsem);
@@ -816,9 +816,9 @@ static int cc3000_open(FAR struct file *filep)
     {
       /* Initialize semaphores */
 
-      sem_init(&priv->waitsem, 0, 0);  /* Initialize event wait semaphore */
-      sem_init(&priv->irqsem, 0, 0);   /* Initialize IRQ Ready semaphore */
-      sem_init(&priv->readysem, 0, 0); /* Initialize Device Ready semaphore */
+      nxsem_init(&priv->waitsem, 0, 0);  /* Initialize event wait semaphore */
+      nxsem_init(&priv->irqsem, 0, 0);   /* Initialize IRQ Ready semaphore */
+      nxsem_init(&priv->readysem, 0, 0); /* Initialize Device Ready semaphore */
 
       /* These semaphores are all used for signaling and, hence, should
        * not have priority inheritance enabled.
@@ -830,7 +830,7 @@ static int cc3000_open(FAR struct file *filep)
 
 #ifdef CONFIG_CC3000_MT
       priv->accepting_socket.acc.sd = FREE_SLOT;
-      sem_init(&priv->accepting_socket.acc.semwait, 0, 0);
+      nxsem_init(&priv->accepting_socket.acc.semwait, 0, 0);
       sem_setprotocol(&priv->accepting_socket.acc.semwait, SEM_PRIO_NONE);
 
       for (s = 0; s < CONFIG_WL_MAX_SOCKETS; s++)
@@ -839,7 +839,7 @@ static int cc3000_open(FAR struct file *filep)
           priv->sockets[s].received_closed_event = false;
           priv->sockets[s].emptied_and_remotely_closed = false;
 
-          sem_init(&priv->sockets[s].semwait, 0, 0);
+          nxsem_init(&priv->sockets[s].semwait, 0, 0);
           sem_setprotocol(&priv->sockets[s].semwait, SEM_PRIO_NONE);
         }
 #endif
@@ -889,7 +889,7 @@ static int cc3000_open(FAR struct file *filep)
       param.sched_priority = CONFIG_CC3000_SELECT_THREAD_PRIORITY;
       pthread_attr_setschedparam(&tattr, &param);
 
-      sem_init(&priv->selectsem, 0, 0);
+      nxsem_init(&priv->selectsem, 0, 0);
       sem_setprotocol(&priv->selectsem, SEM_PRIO_NONE);
 
       ret = pthread_create(&priv->selecttid, &tattr, select_thread_func,
@@ -1551,7 +1551,7 @@ int cc3000_register(FAR struct spi_dev_s *spi,
 
   priv->rx_buffer_max_len = config->max_rx_size;
 
-  sem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
+  nxsem_init(&priv->devsem,  0, 1);    /* Initialize device structure semaphore */
 
   (void)snprintf(semname, SEM_NAMELEN, SEM_FORMAT, minor);
   priv->wrkwaitsem = sem_open(semname, O_CREAT, 0, 0); /* Initialize  Worker Wait semaphore */
diff --git a/drivers/wireless/cc3000/cc3000drv.c b/drivers/wireless/cc3000/cc3000drv.c
index 6327371a47..0a099a9c9f 100644
--- a/drivers/wireless/cc3000/cc3000drv.c
+++ b/drivers/wireless/cc3000/cc3000drv.c
@@ -242,7 +242,7 @@ void cc3000_open(gcSpiHandleRx pfRxHandler)
       spiconf.cc3000fd = fd;
       spiconf.run = true;
 
-      sem_init(&spiconf.unsoliced_thread_wakesem, 0, 0);
+      nxsem_init(&spiconf.unsoliced_thread_wakesem, 0, 0);
 
       pthread_attr_t attr;
       struct sched_param param;
diff --git a/drivers/wireless/ieee80211/bcmf_driver.c b/drivers/wireless/ieee80211/bcmf_driver.c
index d9c389f820..ae63d19cdf 100644
--- a/drivers/wireless/ieee80211/bcmf_driver.c
+++ b/drivers/wireless/ieee80211/bcmf_driver.c
@@ -137,12 +137,12 @@ FAR struct bcmf_dev_s *bcmf_allocate_device(void)
 
   /* Init control frames mutex and timeout signal */
 
-  if ((ret = sem_init(&priv->control_mutex, 0, 1)) != OK)
+  if ((ret = nxsem_init(&priv->control_mutex, 0, 1)) != OK)
     {
       goto exit_free_priv;
     }
 
-  if ((ret = sem_init(&priv->control_timeout, 0, 0)) != OK)
+  if ((ret = nxsem_init(&priv->control_timeout, 0, 0)) != OK)
     {
       goto exit_free_priv;
     }
@@ -154,7 +154,7 @@ FAR struct bcmf_dev_s *bcmf_allocate_device(void)
 
   /* Init authentication signal semaphore */
 
-  if ((ret = sem_init(&priv->auth_signal, 0, 0)) != OK)
+  if ((ret = nxsem_init(&priv->auth_signal, 0, 0)) != OK)
     {
       goto exit_free_priv;
     }
diff --git a/drivers/wireless/ieee80211/bcmf_sdio.c b/drivers/wireless/ieee80211/bcmf_sdio.c
index dcef6fc66e..bad60094b2 100644
--- a/drivers/wireless/ieee80211/bcmf_sdio.c
+++ b/drivers/wireless/ieee80211/bcmf_sdio.c
@@ -581,7 +581,7 @@ int bcmf_bus_sdio_initialize(FAR struct bcmf_dev_s *priv,
 
   /* Init transmit frames queue */
 
-  if ((ret = sem_init(&sbus->queue_mutex, 0, 1)) != OK)
+  if ((ret = nxsem_init(&sbus->queue_mutex, 0, 1)) != OK)
     {
       goto exit_free_bus;
     }
@@ -600,7 +600,7 @@ int bcmf_bus_sdio_initialize(FAR struct bcmf_dev_s *priv,
 
   /* Init thread semaphore */
 
-  if ((ret = sem_init(&sbus->thread_signal, 0, 0)) != OK)
+  if ((ret = nxsem_init(&sbus->thread_signal, 0, 0)) != OK)
     {
       goto exit_free_bus;
     }
diff --git a/drivers/wireless/ieee802154/at86rf23x/at86rf23x.c b/drivers/wireless/ieee802154/at86rf23x/at86rf23x.c
index 1fe4250d3a..a99a01496f 100644
--- a/drivers/wireless/ieee802154/at86rf23x/at86rf23x.c
+++ b/drivers/wireless/ieee802154/at86rf23x/at86rf23x.c
@@ -1492,8 +1492,8 @@ FAR struct ieee802154_radio_s *at86rf23x_init(FAR struct spi_dev_s *spi,
       return NULL;
     }
 
-  sem_init(&dev->ieee.rxsem, 0, 0);
-  sem_init(&dev->ieee.txsem, 0, 0);
+  nxsem_init(&dev->ieee.rxsem, 0, 0);
+  nxsem_init(&dev->ieee.txsem, 0, 0);
 
   /* Initialize device */
 
diff --git a/drivers/wireless/ieee802154/mrf24j40/mrf24j40.c b/drivers/wireless/ieee802154/mrf24j40/mrf24j40.c
index 2d1fc5ffe6..55f026ce7e 100644
--- a/drivers/wireless/ieee802154/mrf24j40/mrf24j40.c
+++ b/drivers/wireless/ieee802154/mrf24j40/mrf24j40.c
@@ -448,7 +448,7 @@ FAR struct ieee802154_radio_s *mrf24j40_init(FAR struct spi_dev_s *spi,
 
   /* Allow exclusive access to the privmac struct */
 
-  sem_init(&dev->exclsem, 0, 1);
+  nxsem_init(&dev->exclsem, 0, 1);
 
   dev->radio.bind         = mrf24j40_bind;
   dev->radio.reset        = mrf24j40_reset;
diff --git a/drivers/wireless/ieee802154/xbee/xbee.c b/drivers/wireless/ieee802154/xbee/xbee.c
index 81a9a6f852..97c4ce6b49 100644
--- a/drivers/wireless/ieee802154/xbee/xbee.c
+++ b/drivers/wireless/ieee802154/xbee/xbee.c
@@ -862,7 +862,7 @@ XBEEHANDLE xbee_init(FAR struct spi_dev_s *spi,
 
   /* Allow exclusive access to the struct */
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 
   /* Initialize the data indication and notifcation allocation pools */
 
@@ -1135,7 +1135,7 @@ void xbee_query_firmwareversion(FAR struct xbee_priv_s *priv)
   struct xbee_respwaiter_s respwaiter;
 
   respwaiter.resp_id = XBEE_RESP_AT_FIRMWAREVERSION;
-  sem_init(&respwaiter.sem, 0, 0);
+  nxsem_init(&respwaiter.sem, 0, 0);
   sem_setprotocol(&respwaiter.sem, SEM_PRIO_NONE);
 
   xbee_register_respwaiter(priv, &respwaiter);
@@ -1162,7 +1162,7 @@ void xbee_query_panid(FAR struct xbee_priv_s *priv)
   struct xbee_respwaiter_s respwaiter;
 
   respwaiter.resp_id = XBEE_RESP_AT_NETWORKID;
-  sem_init(&respwaiter.sem, 0, 0);
+  nxsem_init(&respwaiter.sem, 0, 0);
   sem_setprotocol(&respwaiter.sem, SEM_PRIO_NONE);
 
   xbee_register_respwaiter(priv, &respwaiter);
@@ -1189,7 +1189,7 @@ void xbee_query_eaddr(FAR struct xbee_priv_s *priv)
   struct xbee_respwaiter_s respwaiter;
 
   respwaiter.resp_id = XBEE_RESP_AT_SERIALHIGH;
-  sem_init(&respwaiter.sem, 0, 0);
+  nxsem_init(&respwaiter.sem, 0, 0);
   sem_setprotocol(&respwaiter.sem, SEM_PRIO_NONE);
 
   xbee_register_respwaiter(priv, &respwaiter);
@@ -1220,7 +1220,7 @@ void xbee_query_saddr(FAR struct xbee_priv_s *priv)
   struct xbee_respwaiter_s respwaiter;
 
   respwaiter.resp_id = XBEE_RESP_AT_SOURCEADDR;
-  sem_init(&respwaiter.sem, 0, 0);
+  nxsem_init(&respwaiter.sem, 0, 0);
   sem_setprotocol(&respwaiter.sem, SEM_PRIO_NONE);
 
   xbee_register_respwaiter(priv, &respwaiter);
@@ -1247,7 +1247,7 @@ void xbee_query_chan(FAR struct xbee_priv_s *priv)
   struct xbee_respwaiter_s respwaiter;
 
   respwaiter.resp_id = XBEE_RESP_AT_CHAN;
-  sem_init(&respwaiter.sem, 0, 0);
+  nxsem_init(&respwaiter.sem, 0, 0);
   sem_setprotocol(&respwaiter.sem, SEM_PRIO_NONE);
 
   xbee_register_respwaiter(priv, &respwaiter);
diff --git a/drivers/wireless/ieee802154/xbee/xbee_dataind.c b/drivers/wireless/ieee802154/xbee/xbee_dataind.c
index fe2c155263..f800aefd3d 100644
--- a/drivers/wireless/ieee802154/xbee/xbee_dataind.c
+++ b/drivers/wireless/ieee802154/xbee/xbee_dataind.c
@@ -115,7 +115,7 @@ void xbee_dataindpool_init(FAR struct xbee_priv_s *priv)
       remaining--;
     }
 
-  sem_init(&priv->dataind_sem, 0, CONFIG_XBEE_NDATAIND);
+  nxsem_init(&priv->dataind_sem, 0, CONFIG_XBEE_NDATAIND);
 }
 
 /****************************************************************************
diff --git a/drivers/wireless/ieee802154/xbee/xbee_netdev.c b/drivers/wireless/ieee802154/xbee/xbee_netdev.c
index 7e0b30ce14..d0dc387b73 100644
--- a/drivers/wireless/ieee802154/xbee/xbee_netdev.c
+++ b/drivers/wireless/ieee802154/xbee/xbee_netdev.c
@@ -1455,7 +1455,7 @@ int xbee_netdev_register(XBEEHANDLE xbee)
 
   /* Setup a locking semaphore for exclusive device driver access */
 
-  sem_init(&priv->xd_exclsem, 0, 1);
+  nxsem_init(&priv->xd_exclsem, 0, 1);
 
   DEBUGASSERT(priv->xd_txpoll != NULL);
 
@@ -1472,7 +1472,7 @@ int xbee_netdev_register(XBEEHANDLE xbee)
   /* Initialize fields related to MAC event handling */
 
   priv->xd_eventpending = false;
-  sem_init(&priv->xd_eventsem, 0, 0);
+  nxsem_init(&priv->xd_eventsem, 0, 0);
   sem_setprotocol(&priv->xd_eventsem, SEM_PRIO_NONE);
 
   priv->xd_eventhead = NULL;
diff --git a/drivers/wireless/ieee802154/xbee/xbee_notif.c b/drivers/wireless/ieee802154/xbee/xbee_notif.c
index a59a1e3a20..2748a23b4d 100644
--- a/drivers/wireless/ieee802154/xbee/xbee_notif.c
+++ b/drivers/wireless/ieee802154/xbee/xbee_notif.c
@@ -120,7 +120,7 @@ void xbee_notifpool_init(FAR struct xbee_priv_s *priv)
       remaining--;
     }
 
-  sem_init(&priv->notif_sem, 0, CONFIG_XBEE_NNOTIF);
+  nxsem_init(&priv->notif_sem, 0, CONFIG_XBEE_NNOTIF);
 }
 
 /****************************************************************************
diff --git a/drivers/wireless/nrf24l01.c b/drivers/wireless/nrf24l01.c
index 463857e2ef..7d54738fb3 100644
--- a/drivers/wireless/nrf24l01.c
+++ b/drivers/wireless/nrf24l01.c
@@ -863,8 +863,8 @@ static int dosend(FAR struct nrf24l01_dev_s *dev, FAR const uint8_t *data,
 
   /* Wait for IRQ (TX_DS or MAX_RT) - but don't hang on lost IRQ */
 
-  result = sem_tickwait(&dev->sem_tx, clock_systimer(),
-                        MSEC2TICK(NRF24L01_MAX_TX_IRQ_WAIT));
+  result = nxsem_tickwait(&dev->sem_tx, clock_systimer(),
+                          MSEC2TICK(NRF24L01_MAX_TX_IRQ_WAIT));
 
   /* Re-acquire the SPI bus */
 
@@ -1468,14 +1468,14 @@ int nrf24l01_register(FAR struct spi_dev_s *spi,
   dev->en_aa      = 0;
   dev->ce_enabled = false;
 
-  sem_init(&(dev->devsem), 0, 1);
+  nxsem_init(&(dev->devsem), 0, 1);
   dev->nopens     = 0;
 
 #ifndef CONFIG_DISABLE_POLL
   dev->pfd        = NULL;
 #endif
 
-  sem_init(&dev->sem_tx, 0, 0);
+  nxsem_init(&dev->sem_tx, 0, 0);
   sem_setprotocol(&dev->sem_tx, SEM_PRIO_NONE);
 
 #ifdef CONFIG_WL_NRF24L01_RXSUPPORT
@@ -1490,8 +1490,8 @@ int nrf24l01_register(FAR struct spi_dev_s *spi,
   dev->nxt_write  = 0;
   dev->fifo_len   = 0;
 
-  sem_init(&(dev->sem_fifo), 0, 1);
-  sem_init(&(dev->sem_rx), 0, 0);
+  nxsem_init(&(dev->sem_fifo), 0, 1);
+  nxsem_init(&(dev->sem_rx), 0, 0);
   sem_setprotocol(&dev->sem_rx, SEM_PRIO_NONE);
 #endif
 
diff --git a/drivers/wireless/spirit/drivers/spirit_netdev.c b/drivers/wireless/spirit/drivers/spirit_netdev.c
index d9c43bd6af..a01ae167b2 100644
--- a/drivers/wireless/spirit/drivers/spirit_netdev.c
+++ b/drivers/wireless/spirit/drivers/spirit_netdev.c
@@ -2797,8 +2797,8 @@ int spirit_netdev_initialize(FAR struct spi_dev_s *spi,
 
   DEBUGASSERT(priv->txpoll != NULL && priv->txtimeout != NULL);
 
-  sem_init(&priv->rxsem, 0, 1);            /* Access to RX packet queue */
-  sem_init(&priv->txsem, 0, 1);            /* Access to TX packet queue */
+  nxsem_init(&priv->rxsem, 0, 1);            /* Access to RX packet queue */
+  nxsem_init(&priv->txsem, 0, 1);            /* Access to TX packet queue */
 
   /* Initialize the IEEE 802.15.4 network device fields */
 
diff --git a/fs/aio/aio_initialize.c b/fs/aio/aio_initialize.c
index 8d30d6f54a..5c3fd00a5f 100644
--- a/fs/aio/aio_initialize.c
+++ b/fs/aio/aio_initialize.c
@@ -108,8 +108,8 @@ void aio_initialize(void)
 
   /* Initialize counting semaphores */
 
-  (void)sem_init(&g_aioc_freesem, 0, CONFIG_FS_NAIOC);
-  (void)sem_init(&g_aio_exclsem, 0, 1);
+  (void)nxsem_init(&g_aioc_freesem, 0, CONFIG_FS_NAIOC);
+  (void)nxsem_init(&g_aio_exclsem, 0, 1);
 
   g_aio_holder = INVALID_PROCESS_ID;
 
diff --git a/fs/fat/fs_fat32.c b/fs/fat/fs_fat32.c
index 7c0c610332..b9a743ff07 100644
--- a/fs/fat/fs_fat32.c
+++ b/fs/fat/fs_fat32.c
@@ -1948,8 +1948,8 @@ static int fat_bind(FAR struct inode *blkdriver, FAR const void *data,
    * have to addref() here (but does have to release in unbind().
    */
 
-  fs->fs_blkdriver = blkdriver;  /* Save the block driver reference */
-  sem_init(&fs->fs_sem, 0, 0);   /* Initialize the semaphore that controls access */
+  fs->fs_blkdriver = blkdriver;   /* Save the block driver reference */
+  nxsem_init(&fs->fs_sem, 0, 0);  /* Initialize the semaphore that controls access */
 
   /* Then get information about the FAT32 filesystem on the devices managed
    * by this block driver.
diff --git a/fs/hostfs/hostfs.c b/fs/hostfs/hostfs.c
index 057544f698..4bb789b49e 100644
--- a/fs/hostfs/hostfs.c
+++ b/fs/hostfs/hostfs.c
@@ -874,7 +874,7 @@ static int hostfs_bind(FAR struct inode *blkdriver, FAR const void *data,
     {
       /* Initialize the semaphore that controls access */
 
-      sem_init(&g_sem, 0, 0);
+      nxsem_init(&g_sem, 0, 0);
       g_seminitialized = TRUE;
     }
   else
diff --git a/fs/inode/fs_files.c b/fs/inode/fs_files.c
index 92e93a2936..328949b0d1 100644
--- a/fs/inode/fs_files.c
+++ b/fs/inode/fs_files.c
@@ -151,7 +151,7 @@ void files_initlist(FAR struct filelist *list)
 
   /* Initialize the list access mutex */
 
-  (void)sem_init(&list->fl_sem, 0, 1);
+  (void)nxsem_init(&list->fl_sem, 0, 1);
 }
 
 /****************************************************************************
diff --git a/fs/inode/fs_inode.c b/fs/inode/fs_inode.c
index 8bbeb3f4ec..160e2e00e7 100644
--- a/fs/inode/fs_inode.c
+++ b/fs/inode/fs_inode.c
@@ -98,7 +98,7 @@ void inode_initialize(void)
    * inode tree).
    */
 
-  (void)sem_init(&g_inode_sem.sem, 0, 1);
+  (void)nxsem_init(&g_inode_sem.sem, 0, 1);
   g_inode_sem.holder = NO_HOLDER;
   g_inode_sem.count  = 0;
 
diff --git a/fs/mmap/fs_rammap.c b/fs/mmap/fs_rammap.c
index 5fe71478f5..a12feb2b34 100644
--- a/fs/mmap/fs_rammap.c
+++ b/fs/mmap/fs_rammap.c
@@ -84,7 +84,7 @@ void rammap_initialize(void)
 {
   if (!g_rammaps.initialized)
     {
-      sem_init(&g_rammaps.exclsem, 0, 1);
+      nxsem_init(&g_rammaps.exclsem, 0, 1);
       g_rammaps.initialized = true;
     }
 }
diff --git a/fs/nfs/nfs_vfsops.c b/fs/nfs/nfs_vfsops.c
index f042e78137..f7ac4093e8 100644
--- a/fs/nfs/nfs_vfsops.c
+++ b/fs/nfs/nfs_vfsops.c
@@ -1838,7 +1838,7 @@ static int nfs_bind(FAR struct inode *blkdriver, FAR const void *data,
    * incrementing the count to one.
    */
 
-  sem_init(&nmp->nm_sem, 0, 0);     /* Initialize the semaphore that controls access */
+  nxsem_init(&nmp->nm_sem, 0, 0);   /* Initialize the semaphore that controls access */
 
   /* Initialize NFS */
 
diff --git a/fs/nxffs/nxffs_initialize.c b/fs/nxffs/nxffs_initialize.c
index bf511c8186..f2518569fe 100644
--- a/fs/nxffs/nxffs_initialize.c
+++ b/fs/nxffs/nxffs_initialize.c
@@ -180,8 +180,8 @@ int nxffs_initialize(FAR struct mtd_dev_s *mtd)
 
   volume->mtd    = mtd;
   volume->cblock = (off_t)-1;
-  sem_init(&volume->exclsem, 0, 1);
-  sem_init(&volume->wrsem, 0, 1);
+  nxsem_init(&volume->exclsem, 0, 1);
+  nxsem_init(&volume->wrsem, 0, 1);
 
   /* Get the volume geometry. (casting to uintptr_t first eliminates
    * complaints on some architectures where the sizeof long is different
diff --git a/fs/romfs/fs_romfs.c b/fs/romfs/fs_romfs.c
index 083f5760d0..439fcc2b0b 100644
--- a/fs/romfs/fs_romfs.c
+++ b/fs/romfs/fs_romfs.c
@@ -992,7 +992,7 @@ static int romfs_bind(FAR struct inode *blkdriver, FAR const void *data,
    * have to addref() here (but does have to release in ubind().
    */
 
-  sem_init(&rm->rm_sem, 0, 0);     /* Initialize the semaphore that controls access */
+  nxsem_init(&rm->rm_sem, 0, 0);   /* Initialize the semaphore that controls access */
   rm->rm_blkdriver   = blkdriver;  /* Save the block driver reference */
 
   /* Get the hardware configuration and setup buffering appropriately */
diff --git a/fs/semaphore/sem_open.c b/fs/semaphore/sem_open.c
index 4055b66ba7..4bc91daeb0 100644
--- a/fs/semaphore/sem_open.c
+++ b/fs/semaphore/sem_open.c
@@ -239,7 +239,7 @@ FAR sem_t *sem_open (FAR const char *name, int oflags, ...)
 
       /* Initialize the semaphore */
 
-      sem_init(&nsem->ns_sem, 0, value);
+      nxsem_init(&nsem->ns_sem, 0, value);
 
       /* Return a reference to the semaphore */
 
diff --git a/fs/smartfs/smartfs_smart.c b/fs/smartfs/smartfs_smart.c
index db358e4ae6..3516c4b28f 100644
--- a/fs/smartfs/smartfs_smart.c
+++ b/fs/smartfs/smartfs_smart.c
@@ -1564,7 +1564,7 @@ static int smartfs_bind(FAR struct inode *blkdriver, const void *data,
   fs->fs_sem = &g_sem;
   if (!g_seminitialized)
     {
-      sem_init(&g_sem, 0, 0);   /* Initialize the semaphore that controls access */
+      nxsem_init(&g_sem, 0, 0);  /* Initialize the semaphore that controls access */
       g_seminitialized = TRUE;
     }
   else
diff --git a/fs/tmpfs/fs_tmpfs.c b/fs/tmpfs/fs_tmpfs.c
index 4da971f3c0..c27ba9400a 100644
--- a/fs/tmpfs/fs_tmpfs.c
+++ b/fs/tmpfs/fs_tmpfs.c
@@ -634,7 +634,7 @@ static FAR struct tmpfs_file_s *tmpfs_alloc_file(void)
 
   tfo->tfo_exclsem.ts_holder = getpid();
   tfo->tfo_exclsem.ts_count  = 1;
-  sem_init(&tfo->tfo_exclsem.ts_sem, 0, 0);
+  nxsem_init(&tfo->tfo_exclsem.ts_sem, 0, 0);
 
   return tfo;
 }
@@ -792,7 +792,7 @@ static FAR struct tmpfs_directory_s *tmpfs_alloc_directory(void)
 
   tdo->tdo_exclsem.ts_holder = TMPFS_NO_HOLDER;
   tdo->tdo_exclsem.ts_count  = 0;
-  sem_init(&tdo->tdo_exclsem.ts_sem, 0, 1);
+  nxsem_init(&tdo->tdo_exclsem.ts_sem, 0, 1);
 
   return tdo;
 }
@@ -2014,7 +2014,7 @@ static int tmpfs_bind(FAR struct inode *blkdriver, FAR const void *data,
 
   fs->tfs_exclsem.ts_holder = TMPFS_NO_HOLDER;
   fs->tfs_exclsem.ts_count  = 0;
-  sem_init(&fs->tfs_exclsem.ts_sem, 0, 1);
+  nxsem_init(&fs->tfs_exclsem.ts_sem, 0, 1);
 
   /* Return the new file system handle */
 
diff --git a/fs/unionfs/fs_unionfs.c b/fs/unionfs/fs_unionfs.c
index 41ba128c9b..f5b2a9be96 100644
--- a/fs/unionfs/fs_unionfs.c
+++ b/fs/unionfs/fs_unionfs.c
@@ -2593,7 +2593,7 @@ int unionfs_mount(FAR const char *fspath1, FAR const char *prefix1,
       return -ENOMEM;
     }
 
-  sem_init(&ui->ui_exclsem, 0, 1);
+  nxsem_init(&ui->ui_exclsem, 0, 1);
 
   /* Get the inodes associated with fspath1 and fspath2 */
 
diff --git a/fs/vfs/fs_fdopen.c b/fs/vfs/fs_fdopen.c
index ebacc4c5ff..81e535756c 100644
--- a/fs/vfs/fs_fdopen.c
+++ b/fs/vfs/fs_fdopen.c
@@ -226,7 +226,7 @@ FAR struct file_struct *fs_fdopen(int fd, int oflags, FAR struct tcb_s *tcb)
 #ifndef CONFIG_STDIO_DISABLE_BUFFERING
           /* Initialize the semaphore the manages access to the buffer */
 
-          (void)sem_init(&stream->fs_sem, 0, 1);
+          (void)nxsem_init(&stream->fs_sem, 0, 1);
 
 #if CONFIG_STDIO_BUFFER_SIZE > 0
           /* Allocate the IO buffer at the appropriate privilege level for
diff --git a/fs/vfs/fs_poll.c b/fs/vfs/fs_poll.c
index 13b82635bc..1095d875e4 100644
--- a/fs/vfs/fs_poll.c
+++ b/fs/vfs/fs_poll.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * fs/vfs/fs_poll.c
  *
- *   Copyright (C) 2008-2009, 2012-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2009, 2012-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -397,7 +397,7 @@ int poll(FAR struct pollfd *fds, nfds_t nfds, int timeout)
    * priority inheritance enabled.
    */
 
-  sem_init(&sem, 0, 0);
+  nxsem_init(&sem, 0, 0);
   sem_setprotocol(&sem, SEM_PRIO_NONE);
 
   ret = poll_setup(fds, nfds, &sem);
@@ -434,11 +434,11 @@ int poll(FAR struct pollfd *fds, nfds_t nfds, int timeout)
            * or for the specified timeout to elapse with no event.
            *
            * NOTE: If a poll event is pending (i.e., the semaphore has already
-           * been incremented), sem_tickwait() will not wait, but will return
+           * been incremented), nxsem_tickwait() will not wait, but will return
            * immediately.
            */
 
-           ret = sem_tickwait(&sem, clock_systimer(), ticks);
+           ret = nxsem_tickwait(&sem, clock_systimer(), ticks);
            if (ret < 0)
              {
                if (ret == -ETIMEDOUT)
diff --git a/graphics/nxterm/nxterm_register.c b/graphics/nxterm/nxterm_register.c
index a83e84cffc..2dfcfc2f51 100644
--- a/graphics/nxterm/nxterm_register.c
+++ b/graphics/nxterm/nxterm_register.c
@@ -89,7 +89,7 @@ FAR struct nxterm_state_s *
   priv->minor   = minor;
   memcpy(&priv->wndo, wndo, sizeof(struct nxterm_window_s));
 
-  sem_init(&priv->exclsem, 0, 1);
+  nxsem_init(&priv->exclsem, 0, 1);
 #ifdef CONFIG_DEBUG_FEATURES
   priv->holder  = NO_HOLDER;
 #endif
@@ -99,7 +99,7 @@ FAR struct nxterm_state_s *
    * priority inheritance enabled.
    */
 
-  sem_init(&priv->waitsem, 0, 0);
+  nxsem_init(&priv->waitsem, 0, 0);
   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
 
diff --git a/graphics/vnc/server/vnc_fbdev.c b/graphics/vnc/server/vnc_fbdev.c
index 5517a30e9f..00b171b70b 100644
--- a/graphics/vnc/server/vnc_fbdev.c
+++ b/graphics/vnc/server/vnc_fbdev.c
@@ -443,8 +443,8 @@ static int vnc_start_server(int display)
   ginfo("Starting the VNC server for display %d\n", display);
 
   g_fbstartup[display].result = -EBUSY;
-  sem_reset(&g_fbstartup[display].fbinit, 0);
-  sem_reset(&g_fbstartup[display].fbconnect, 0);
+  nxsem_reset(&g_fbstartup[display].fbinit, 0);
+  nxsem_reset(&g_fbstartup[display].fbconnect, 0);
 
   /* Format the kernel thread arguments (ASCII.. yech) */
 
diff --git a/graphics/vnc/server/vnc_server.c b/graphics/vnc/server/vnc_server.c
index 99fb929014..c5e94dcd8b 100644
--- a/graphics/vnc/server/vnc_server.c
+++ b/graphics/vnc/server/vnc_server.c
@@ -131,8 +131,8 @@ static void vnc_reset_session(FAR struct vnc_session_s *session,
 
   /* Set the INITIALIZED state */
 
-  sem_reset(&session->freesem, CONFIG_VNCSERVER_NUPDATES);
-  sem_reset(&session->queuesem, 0);
+  nxsem_reset(&session->freesem, CONFIG_VNCSERVER_NUPDATES);
+  nxsem_reset(&session->queuesem, 0);
 
   session->fb      = fb;
   session->display = display;
@@ -291,8 +291,8 @@ int vnc_server(int argc, FAR char *argv[])
     }
 
   g_vnc_sessions[display] = session;
-  sem_init(&session->freesem, 0, CONFIG_VNCSERVER_NUPDATES);
-  sem_init(&session->queuesem, 0, 0);
+  nxsem_init(&session->freesem, 0, CONFIG_VNCSERVER_NUPDATES);
+  nxsem_init(&session->queuesem, 0, 0);
 
   /* Inform any waiter that we have started */
 
@@ -311,7 +311,7 @@ int vnc_server(int argc, FAR char *argv[])
 
       vnc_reset_session(session, fb, display);
       g_fbstartup[display].result = -EBUSY;
-      sem_reset(&g_fbstartup[display].fbconnect, 0);
+      nxsem_reset(&g_fbstartup[display].fbconnect, 0);
 
       /* Establish a connection with the VNC client */
 
diff --git a/graphics/vnc/server/vnc_updater.c b/graphics/vnc/server/vnc_updater.c
index a0c23a0c02..f42d1f93ef 100644
--- a/graphics/vnc/server/vnc_updater.c
+++ b/graphics/vnc/server/vnc_updater.c
@@ -585,7 +585,7 @@ int vnc_update_rectangle(FAR struct vnc_session_s *session,
 
               curr = (FAR struct vnc_fbupdate_s *)session->updqueue.head;
               sq_init(&session->updqueue);
-              sem_reset(&session->queuesem, 0);
+              nxsem_reset(&session->queuesem, 0);
 
               for (; curr != NULL; curr = next)
                 {
diff --git a/include/nuttx/semaphore.h b/include/nuttx/semaphore.h
index fce15b1134..0613e01dbf 100644
--- a/include/nuttx/semaphore.h
+++ b/include/nuttx/semaphore.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * include/nuttx/semaphore.h
  *
- *   Copyright (C) 2014-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -98,7 +98,34 @@ extern "C"
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_tickwait
+ * Name: nxsem_init
+ *
+ * Description:
+ *   This function initializes the UNAMED semaphore sem. Following a
+ *   successful call to nxsem_init(), the semaphore may be used in subsequent
+ *   calls to sem_wait(), sem_post(), and sem_trywait().  The semaphore
+ *   remains usable until it is destroyed.
+ *
+ *   Only sem itself may be used for performing synchronization. The result
+ *   of referring to copies of sem in calls to sem_wait(), sem_trywait(),
+ *   sem_post(), and sem_destroy() is undefined.
+ *
+ * Parameters:
+ *   sem - Semaphore to be initialized
+ *   pshared - Process sharing (not used)
+ *   value - Semaphore initialization value
+ *
+ * Return Value:
+ *   This is an internal OS interface and should not be used byapplications.
+ *   It follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
+ *
+ ****************************************************************************/
+
+int nxsem_init(FAR sem_t *sem, int pshared, unsigned int value);
+
+/****************************************************************************
+ * Name: nxsem_tickwait
  *
  * Description:
  *   This function is a lighter weight version of sem_timedwait().  It is
@@ -115,19 +142,49 @@ extern "C"
  *             to sem_trywait().
  *
  * Return Value:
- *   Zero (OK) is returned on success.  A negated errno value is returned on
- *   failure.  -ETIMEDOUT is returned on the timeout condition.
+ *   This is an internal OS interface, not available to applications, and
+ *   hence follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
+ *   -ETIMEDOUT is returned on the timeout condition.
  *
  ****************************************************************************/
 
-int sem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay);
+int nxsem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay);
 
 /****************************************************************************
- * Name: sem_reset
+ * Name:  nxsem_getvalue
+ *
+ * Description:
+ *   This function updates the location referenced by 'sval' argument to
+ *   have the value of the semaphore referenced by 'sem' without effecting
+ *   the state of the semaphore.  The updated value represents the actual
+ *   semaphore value that occurred at some unspecified time during the call,
+ *   but may not reflect the actual value of the semaphore when it is
+ *   returned to the calling task.
+ *
+ *   If 'sem' is locked, the value return by nxsem_getvalue() will either be
+ *   zero or a negative number whose absolute value represents the number
+ *   of tasks waiting for the semaphore.
+ *
+ * Parameters:
+ *   sem - Semaphore descriptor
+ *   sval - Buffer by which the value is returned
+ *
+ * Return Value:
+ *   This is an internal OS interface and should not be used by applications.
+ *   It follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
+ *
+ ****************************************************************************/
+
+int nxsem_getvalue(FAR sem_t *sem, FAR int *sval);
+
+/****************************************************************************
+ * Name: nxsem_reset
  *
  * Description:
  *   Reset a semaphore count to a specific value.  This is similar to part
- *   of the operation of sem_init().  But sem_reset() may need to wake up
+ *   of the operation of nxsem_init().  But nxsem_reset() may need to wake up
  *   tasks waiting on a count.  This kind of operation is sometimes required
  *   within the OS (only) for certain error handling conditions.
  *
@@ -136,11 +193,13 @@ int sem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay);
  *   count - The requested semaphore count
  *
  * Return Value:
- *   0 (OK) or a negated errno value if unsuccessful
+ *   This is an internal OS interface, not available to applications, and
+ *   hence follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
  *
  ****************************************************************************/
 
-int sem_reset(FAR sem_t *sem, int16_t count);
+int nxsem_reset(FAR sem_t *sem, int16_t count);
 
 /****************************************************************************
  * Name: sem_getprotocol
@@ -155,8 +214,9 @@ int sem_reset(FAR sem_t *sem, int16_t count);
  *               value.
  *
  * Return Value:
- *   0 if successful.  Otherwise, -1 is returned and the errno value is set
- *   appropriately.
+ *   This function is exposed as a non-standard application interface.  It
+ *   returns zero (OK) if successful.  Otherwise, -1 (ERROR) is returned and
+ *   the errno value is set appropriately.
  *
  ****************************************************************************/
 
@@ -193,8 +253,9 @@ int sem_getprotocol(FAR sem_t *sem, FAR int *protocol);
  *    protocol - The new protocol to use
  *
  * Return Value:
- *   0 if successful.  Otherwise, -1 is returned and the errno value is set
- *   appropriately.
+ *   This function is exposed as a non-standard application interface.  It
+ *   returns zero (OK) if successful.  Otherwise, -1 (ERROR) is returned and
+ *   the errno value is set appropriately.
  *
  ****************************************************************************/
 
diff --git a/libc/audio/lib_buffer.c b/libc/audio/lib_buffer.c
index 6ad506aa6e..35e92eead4 100644
--- a/libc/audio/lib_buffer.c
+++ b/libc/audio/lib_buffer.c
@@ -148,7 +148,7 @@ int apb_alloc(FAR struct audio_buf_desc_s *bufdesc)
       apb->session    = bufdesc->session;
 #endif
 
-      sem_init(&apb->sem, 0, 1);
+      nxsem_init(&apb->sem, 0, 1);
       ret = sizeof(struct audio_buf_desc_s);
     }
 
diff --git a/libc/misc/lib_filesem.c b/libc/misc/lib_filesem.c
index 1ea8717146..88b0df355b 100644
--- a/libc/misc/lib_filesem.c
+++ b/libc/misc/lib_filesem.c
@@ -65,7 +65,7 @@ void lib_sem_initialize(FAR struct file_struct *stream)
    * to private data sets.
    */
 
-  (void)sem_init(&stream->fs_sem, 0, 1);
+  (void)nxsem_init(&stream->fs_sem, 0, 1);
 
   stream->fs_holder = -1;
   stream->fs_counts = 0;
diff --git a/libc/misc/lib_stream.c b/libc/misc/lib_stream.c
index 4ed0343345..04149e5809 100644
--- a/libc/misc/lib_stream.c
+++ b/libc/misc/lib_stream.c
@@ -83,7 +83,7 @@ void lib_stream_initialize(FAR struct task_group_s *group)
 
   /* Initialize the list access mutex */
 
-  (void)sem_init(&list->sl_sem, 0, 1);
+  (void)nxsem_init(&list->sl_sem, 0, 1);
 
   /* Initialize each FILE structure */
 
diff --git a/libc/netdb/lib_dnsinit.c b/libc/netdb/lib_dnsinit.c
index b6e0f8d0e0..3b58826133 100644
--- a/libc/netdb/lib_dnsinit.c
+++ b/libc/netdb/lib_dnsinit.c
@@ -94,7 +94,7 @@ bool dns_initialize(void)
 
   if (!g_dns_initialized)
     {
-      sem_init(&g_dns_sem, 0, 1);
+      nxsem_init(&g_dns_sem, 0, 1);
       g_dns_initialized = true;
     }
 
diff --git a/libc/pthread/pthread_barrierinit.c b/libc/pthread/pthread_barrierinit.c
index 6f8d427dfe..63f548cec6 100644
--- a/libc/pthread/pthread_barrierinit.c
+++ b/libc/pthread/pthread_barrierinit.c
@@ -95,7 +95,7 @@ int pthread_barrier_init(FAR pthread_barrier_t *barrier,
     }
   else
     {
-      sem_init(&barrier->sem, 0, 0);
+      nxsem_init(&barrier->sem, 0, 0);
       barrier->count = count;
     }
 
diff --git a/libc/pthread/pthread_barrierwait.c b/libc/pthread/pthread_barrierwait.c
index 8ba29d1d94..dccd83c148 100644
--- a/libc/pthread/pthread_barrierwait.c
+++ b/libc/pthread/pthread_barrierwait.c
@@ -109,7 +109,7 @@ int pthread_barrier_wait(FAR pthread_barrier_t *barrier)
 
   /* Find out how many threads are already waiting at the barrier */
 
-  ret = sem_getvalue(&barrier->sem, &semcount);
+  ret = nxsem_getvalue(&barrier->sem, &semcount);
   if (ret != OK)
     {
       sched_unlock();
@@ -125,7 +125,7 @@ int pthread_barrier_wait(FAR pthread_barrier_t *barrier)
       while (semcount < 0)
         {
           (void)sem_post(&barrier->sem);
-          (void)sem_getvalue(&barrier->sem, &semcount);
+          (void)nxsem_getvalue(&barrier->sem, &semcount);
         }
 
       /* Then return PTHREAD_BARRIER_SERIAL_THREAD to the final thread */
diff --git a/libc/pthread/pthread_condinit.c b/libc/pthread/pthread_condinit.c
index 81a31ea57f..e757817f14 100644
--- a/libc/pthread/pthread_condinit.c
+++ b/libc/pthread/pthread_condinit.c
@@ -81,7 +81,7 @@ int pthread_cond_init(FAR pthread_cond_t *cond, FAR const pthread_condattr_t *at
    * initial count = 0
    */
 
-  else if (sem_init((FAR sem_t *)&cond->sem, 0, 0) != OK)
+  else if (nxsem_init((FAR sem_t *)&cond->sem, 0, 0) != OK)
     {
       ret = EINVAL;
     }
diff --git a/libc/semaphore/sem_getprotocol.c b/libc/semaphore/sem_getprotocol.c
index a9e8a837e1..308f1ea520 100644
--- a/libc/semaphore/sem_getprotocol.c
+++ b/libc/semaphore/sem_getprotocol.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/semaphore/sem_getprotocol.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -60,8 +60,9 @@
  *               value.
  *
  * Return Value:
- *   0 if successful.  Otherwise, -1 is returned and the errno value is set
- *   appropriately.
+ *   This function is exposed as a non-standard application interface.  It
+ *   returns zero (OK) if successful.  Otherwise, -1 (ERROR) is returned and
+ *   the errno value is set appropriately.
  *
  ****************************************************************************/
 
diff --git a/libc/semaphore/sem_getvalue.c b/libc/semaphore/sem_getvalue.c
index f1c77aa6f0..120dae1372 100644
--- a/libc/semaphore/sem_getvalue.c
+++ b/libc/semaphore/sem_getvalue.c
@@ -43,30 +43,49 @@
 #include <semaphore.h>
 #include <errno.h>
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Type Declarations
- ****************************************************************************/
-
-/****************************************************************************
- * Public Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
+#include <nuttx/semaphore.h>
 
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
 
+/****************************************************************************
+ * Name:  nxsem_getvalue
+ *
+ * Description:
+ *   This function updates the location referenced by 'sval' argument to
+ *   have the value of the semaphore referenced by 'sem' without effecting
+ *   the state of the semaphore.  The updated value represents the actual
+ *   semaphore value that occurred at some unspecified time during the call,
+ *   but may not reflect the actual value of the semaphore when it is
+ *   returned to the calling task.
+ *
+ *   If 'sem' is locked, the value return by nxsem_getvalue() will either be
+ *   zero or a negative number whose absolute value represents the number
+ *   of tasks waiting for the semaphore.
+ *
+ * Parameters:
+ *   sem - Semaphore descriptor
+ *   sval - Buffer by which the value is returned
+ *
+ * Return Value:
+ *   This is an internal OS interface and should not be used by applications.
+ *   It follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
+ *
+ ****************************************************************************/
+
+int nxsem_getvalue(FAR sem_t *sem, FAR int *sval)
+{
+  if (sem && sval)
+    {
+      *sval = sem->semcount;
+      return OK;
+    }
+
+  return -EINVAL;
+}
+
 /****************************************************************************
  * Name:  sem_getvalue
  *
@@ -86,23 +105,21 @@
  *   sem - Semaphore descriptor
  *   sval - Buffer by which the value is returned
  *
- * Return Value:
- *   0 (OK), or -1 (ERROR) if unsuccessful
- *
- * Assumptions:
+ *   This returns zero (OK) if successful.  Otherwise, -1 (ERROR) is
+ *   returned and the errno value is set appropriately.
  *
  ****************************************************************************/
 
 int sem_getvalue(FAR sem_t *sem, FAR int *sval)
 {
-  if (sem && sval)
+  int ret;
+
+  ret = nxsem_getvalue(sem, sval);
+  if (ret < 0)
     {
-      *sval = sem->semcount;
-      return OK;
-    }
-  else
-    {
-      set_errno(EINVAL);
-      return ERROR;
+      set_errno(-ret);
+      ret = ERROR;
     }
+
+  return ret;
 }
diff --git a/libc/semaphore/sem_init.c b/libc/semaphore/sem_init.c
index e10e83f1fa..4f9812157b 100644
--- a/libc/semaphore/sem_init.c
+++ b/libc/semaphore/sem_init.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/sem/sem_init.c
  *
- *   Copyright (C) 2007-2009, 2011-2012, 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2012, 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -44,16 +44,18 @@
 #include <semaphore.h>
 #include <errno.h>
 
+#include <nuttx/semaphore.h>
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_init
+ * Name: nxsem_init
  *
  * Description:
  *   This function initializes the UNAMED semaphore sem. Following a
- *   successful call to sem_init(), the semaophore may be used in subsequent
+ *   successful call to nxsem_init(), the semaphore may be used in subsequent
  *   calls to sem_wait(), sem_post(), and sem_trywait().  The semaphore
  *   remains usable until it is destroyed.
  *
@@ -67,19 +69,19 @@
  *   value - Semaphore initialization value
  *
  * Return Value:
- *   0 (OK), or -1 (ERROR) if unsuccessful.
- *
- * Assumptions:
+ *   This is an internal OS interface and should not be used by applications.
+ *   It follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
  *
  ****************************************************************************/
 
-int sem_init(FAR sem_t *sem, int pshared, unsigned int value)
+int nxsem_init(FAR sem_t *sem, int pshared, unsigned int value)
 {
   /* Verify that a semaphore was provided and the count is within the valid
    * range.
    */
 
-  if (sem && value <= SEM_VALUE_MAX)
+  if (sem != NULL && value <= SEM_VALUE_MAX)
     {
       /* Initialize the seamphore count */
 
@@ -100,9 +102,44 @@ int sem_init(FAR sem_t *sem, int pshared, unsigned int value)
 #endif
       return OK;
     }
-  else
-    {
-      set_errno(EINVAL);
-      return ERROR;
-    }
+
+  return -EINVAL;
+}
+
+/****************************************************************************
+ * Name: sem_init
+ *
+ * Description:
+ *   This function initializes the UNAMED semaphore sem. Following a
+ *   successful call to sem_init(), the semaphore may be used in subsequent
+ *   calls to sem_wait(), sem_post(), and sem_trywait().  The semaphore
+ *   remains usable until it is destroyed.
+ *
+ *   Only sem itself may be used for performing synchronization. The result
+ *   of referring to copies of sem in calls to sem_wait(), sem_trywait(),
+ *   sem_post(), and sem_destroy() is undefined.
+ *
+ * Parameters:
+ *   sem - Semaphore to be initialized
+ *   pshared - Process sharing (not used)
+ *   value - Semaphore initialization value
+ *
+ * Return Value:
+ *   This returns zero (OK) if successful.  Otherwise, -1 (ERROR) is
+ *   returned and the errno value is set appropriately.
+ *
+ ****************************************************************************/
+
+int sem_init(FAR sem_t *sem, int pshared, unsigned int value)
+{
+  int ret;
+
+  ret = nxsem_init(sem, pshared, value);
+  if (ret < 0)
+    {
+      set_errno(-ret);
+      ret = ERROR;
+    }
+
+  return ret;
 }
diff --git a/libc/semaphore/sem_setprotocol.c b/libc/semaphore/sem_setprotocol.c
index b687d72280..ede41272d7 100644
--- a/libc/semaphore/sem_setprotocol.c
+++ b/libc/semaphore/sem_setprotocol.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/semaphore/sem_setprotocol.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -81,8 +81,9 @@
  *    protocol - The new protocol to use
  *
  * Return Value:
- *   0 if successful.  Otherwise, -1 is returned and the errno value is set
- *   appropriately.
+ *   This function is exposed as a non-standard application interface.  It
+ *   returns zero (OK) if successful.  Otherwise, -1 (ERROR) is returned and
+ *   the errno value is set appropriately.
  *
  ****************************************************************************/
 
diff --git a/libc/wqueue/work_usrthread.c b/libc/wqueue/work_usrthread.c
index 0f489a7258..833aaf91e5 100644
--- a/libc/wqueue/work_usrthread.c
+++ b/libc/wqueue/work_usrthread.c
@@ -350,7 +350,7 @@ int work_usrstart(void)
   {
     /* Set up the work queue lock */
 
-    (void)sem_init(&g_usrsem, 0, 1);
+    (void)nxsem_init(&g_usrsem, 0, 1);
 
     /* Start a user-mode worker thread for use by applications. */
 
diff --git a/libnx/nxfonts/nxfonts_cache.c b/libnx/nxfonts/nxfonts_cache.c
index b2cdf74da0..0a274ab04a 100644
--- a/libnx/nxfonts/nxfonts_cache.c
+++ b/libnx/nxfonts/nxfonts_cache.c
@@ -748,7 +748,7 @@ FCACHE nxf_cache_connect(enum nx_fontid_e fontid,
 
       /* Initialize the mutual exclusion semaphore */
 
-      sem_init(&priv->fsem, 0, 1);
+      nxsem_init(&priv->fsem, 0, 1);
 
       /* Add the new font cache to the list of font caches */
 
diff --git a/libnx/nxmu/nx_bitmap.c b/libnx/nxmu/nx_bitmap.c
index 9c69291572..f8a0464fa9 100644
--- a/libnx/nxmu/nx_bitmap.c
+++ b/libnx/nxmu/nx_bitmap.c
@@ -115,7 +115,7 @@ int nx_bitmap(NXWINDOW hwnd, FAR const struct nxgl_rect_s *dest,
 
   if (ret != OK)
     {
-      gerr("ERROR: sem_init failed: %d\n", errno);
+      gerr("ERROR: nxsem_init failed: %d\n", errno);
       return ret;
     }
 
diff --git a/libnx/nxmu/nx_getrectangle.c b/libnx/nxmu/nx_getrectangle.c
index 9420d02df5..f84f262943 100644
--- a/libnx/nxmu/nx_getrectangle.c
+++ b/libnx/nxmu/nx_getrectangle.c
@@ -105,11 +105,11 @@ int nx_getrectangle(NXWINDOW hwnd, FAR const struct nxgl_rect_s *rect,
   /* Create a semaphore for tracking command completion */
 
   outmsg.sem_done = &sem_done;
-  ret = sem_init(&sem_done, 0, 0);
 
-  if (ret != OK)
+  ret = sem_init(&sem_done, 0, 0);
+  if (ret < 0)
     {
-      gerr("ERROR: sem_init failed: %d\n", errno);
+      gerr("ERROR: nxsem_init failed: %d\n", errno);
       return ret;
     }
 
diff --git a/mm/iob/iob_initialize.c b/mm/iob/iob_initialize.c
index b11d2f005c..d9ef23154c 100644
--- a/mm/iob/iob_initialize.c
+++ b/mm/iob/iob_initialize.c
@@ -132,9 +132,9 @@ void iob_initialize(void)
 
       g_iob_committed = NULL;
 
-      sem_init(&g_iob_sem, 0, CONFIG_IOB_NBUFFERS);
+      nxsem_init(&g_iob_sem, 0, CONFIG_IOB_NBUFFERS);
 #if CONFIG_IOB_THROTTLE > 0
-      sem_init(&g_throttle_sem, 0, CONFIG_IOB_NBUFFERS - CONFIG_IOB_THROTTLE);
+      nxsem_init(&g_throttle_sem, 0, CONFIG_IOB_NBUFFERS - CONFIG_IOB_THROTTLE);
 #endif
 
 #if CONFIG_IOB_NCHAINS > 0
@@ -152,7 +152,7 @@ void iob_initialize(void)
 
       g_iob_qcommitted = NULL;
 
-      sem_init(&g_qentry_sem, 0, CONFIG_IOB_NCHAINS);
+      nxsem_init(&g_qentry_sem, 0, CONFIG_IOB_NCHAINS);
 #endif
       initialized = true;
     }
diff --git a/mm/mm_gran/mm_graninit.c b/mm/mm_gran/mm_graninit.c
index 03cde59b11..87a7992dd7 100644
--- a/mm/mm_gran/mm_graninit.c
+++ b/mm/mm_gran/mm_graninit.c
@@ -135,7 +135,7 @@ gran_common_initialize(FAR void *heapstart, size_t heapsize, uint8_t log2gran,
       /* Initialize mutual exclusion support */
 
 #ifndef CONFIG_GRAN_INTR
-      sem_init(&priv->exclsem, 0, 1);
+      nxsem_init(&priv->exclsem, 0, 1);
 #endif
     }
 
diff --git a/mm/mm_heap/mm_sem.c b/mm/mm_heap/mm_sem.c
index 49083da213..65bd6e54e7 100644
--- a/mm/mm_heap/mm_sem.c
+++ b/mm/mm_heap/mm_sem.c
@@ -43,6 +43,7 @@
 #include <errno.h>
 #include <assert.h>
 
+#include <nuttx/semaphore.h>
 #include <nuttx/mm/mm.h>
 
 /****************************************************************************
@@ -87,7 +88,7 @@ void mm_seminitialize(FAR struct mm_heap_s *heap)
    * private data sets).
    */
 
-  (void)sem_init(&heap->mm_semaphore, 0, 1);
+  (void)nxsem_init(&heap->mm_semaphore, 0, 1);
 
   heap->mm_holder      = -1;
   heap->mm_counts_held = 0;
diff --git a/mm/shm/shm_initialize.c b/mm/shm/shm_initialize.c
index f20e7b0873..633ad556c8 100644
--- a/mm/shm/shm_initialize.c
+++ b/mm/shm/shm_initialize.c
@@ -87,7 +87,7 @@ void shm_initialize(void)
 
   /* Initialize the shared memory region list */
 
-  sem_init(&g_shminfo.si_sem, 0, 1);
+  nxsem_init(&g_shminfo.si_sem, 0, 1);
 
 #if 0
   /* Initialize each shared memory region */
diff --git a/mm/shm/shmget.c b/mm/shm/shmget.c
index 460850605a..4a961b241b 100644
--- a/mm/shm/shmget.c
+++ b/mm/shm/shmget.c
@@ -122,7 +122,7 @@ static int shm_reserve(key_t key, int shmflg)
           region->sr_key   = key;
           region->sr_flags = SRFLAG_INUSE;
 
-          sem_init(&region->sr_sem, 0, 1);
+          nxsem_init(&region->sr_sem, 0, 1);
 
           /* Set the low-order nine bits of shm_perm.mode to the low-order
            * nine bits of shmflg.
diff --git a/net/arp/arp_notify.c b/net/arp/arp_notify.c
index e59bca3a55..5ebc809667 100644
--- a/net/arp/arp_notify.c
+++ b/net/arp/arp_notify.c
@@ -94,7 +94,7 @@ void arp_wait_setup(in_addr_t ipaddr, FAR struct arp_notify_s *notify)
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&notify->nt_sem, 0, 0);
+  (void)nxsem_init(&notify->nt_sem, 0, 0);
   sem_setprotocol(&notify->nt_sem, SEM_PRIO_NONE);
 
   /* Add the wait structure to the list with interrupts disabled */
diff --git a/net/arp/arp_send.c b/net/arp/arp_send.c
index 9f3416cca3..134a5d720e 100644
--- a/net/arp/arp_send.c
+++ b/net/arp/arp_send.c
@@ -290,7 +290,7 @@ int arp_send(in_addr_t ipaddr)
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
   sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   state.snd_retries   = 0;              /* No retries yet */
diff --git a/net/icmp/icmp_ping.c b/net/icmp/icmp_ping.c
index fbf781a211..c977d5f65d 100644
--- a/net/icmp/icmp_ping.c
+++ b/net/icmp/icmp_ping.c
@@ -365,7 +365,7 @@ int icmp_ping(in_addr_t addr, uint16_t id, uint16_t seqno, uint16_t datalen,
    * priority inheritance enabled.
    */
 
-  sem_init(&state.png_sem, 0, 0);
+  nxsem_init(&state.png_sem, 0, 0);
   sem_setprotocol(&state.png_sem, SEM_PRIO_NONE);
 
   state.png_ticks  = DSEC2TICK(dsecs); /* System ticks to wait */
diff --git a/net/icmpv6/icmpv6_autoconfig.c b/net/icmpv6/icmpv6_autoconfig.c
index a295d58163..ea9e590d49 100644
--- a/net/icmpv6/icmpv6_autoconfig.c
+++ b/net/icmpv6/icmpv6_autoconfig.c
@@ -212,7 +212,7 @@ static int icmpv6_send_message(FAR struct net_driver_s *dev, bool advertise)
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
   sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   /* Remember the routing device name */
diff --git a/net/icmpv6/icmpv6_neighbor.c b/net/icmpv6/icmpv6_neighbor.c
index 64d8ac70bf..6c5e6e1839 100644
--- a/net/icmpv6/icmpv6_neighbor.c
+++ b/net/icmpv6/icmpv6_neighbor.c
@@ -300,7 +300,7 @@ int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.snd_sem, 0, 0);        /* Doesn't really fail */
+  (void)nxsem_init(&state.snd_sem, 0, 0);        /* Doesn't really fail */
   sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   state.snd_retries = 0;                       /* No retries yet */
diff --git a/net/icmpv6/icmpv6_notify.c b/net/icmpv6/icmpv6_notify.c
index 2a0ce43690..5a192b2adc 100644
--- a/net/icmpv6/icmpv6_notify.c
+++ b/net/icmpv6/icmpv6_notify.c
@@ -107,7 +107,7 @@ void icmpv6_wait_setup(const net_ipv6addr_t ipaddr,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&notify->nt_sem, 0, 0);
+  (void)nxsem_init(&notify->nt_sem, 0, 0);
   sem_setprotocol(&notify->nt_sem, SEM_PRIO_NONE);
 
   /* Add the wait structure to the list with interrupts disabled */
diff --git a/net/icmpv6/icmpv6_ping.c b/net/icmpv6/icmpv6_ping.c
index 43427f3cc6..79d718a328 100644
--- a/net/icmpv6/icmpv6_ping.c
+++ b/net/icmpv6/icmpv6_ping.c
@@ -439,7 +439,7 @@ int icmpv6_ping(net_ipv6addr_t addr, uint16_t id, uint16_t seqno,
    * priority inheritance enabled.
    */
 
-  sem_init(&state.png_sem, 0, 0);
+  nxsem_init(&state.png_sem, 0, 0);
   sem_setprotocol(&state.png_sem, SEM_PRIO_NONE);
 
   state.png_ticks  = DSEC2TICK(dsecs);     /* System ticks to wait */
diff --git a/net/icmpv6/icmpv6_rnotify.c b/net/icmpv6/icmpv6_rnotify.c
index 74409ccd3c..b2e0df5ae1 100644
--- a/net/icmpv6/icmpv6_rnotify.c
+++ b/net/icmpv6/icmpv6_rnotify.c
@@ -171,7 +171,7 @@ void icmpv6_rwait_setup(FAR struct net_driver_s *dev,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&notify->rn_sem, 0, 0);
+  (void)nxsem_init(&notify->rn_sem, 0, 0);
   sem_setprotocol(&notify->rn_sem, SEM_PRIO_NONE);
 
   /* Add the wait structure to the list with interrupts disabled */
diff --git a/net/ieee802154/ieee802154_recvfrom.c b/net/ieee802154/ieee802154_recvfrom.c
index 3f13ab98f6..b1ee51500b 100644
--- a/net/ieee802154/ieee802154_recvfrom.c
+++ b/net/ieee802154/ieee802154_recvfrom.c
@@ -380,7 +380,7 @@ ssize_t ieee802154_recvfrom(FAR struct socket *psock, FAR void *buf,
    * hence, should not have priority inheritance enabled.
    */
 
-  (void)sem_init(&state.ir_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&state.ir_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&state.ir_sem, SEM_PRIO_NONE);
 
   /* Set the socket state to receiving */
diff --git a/net/ieee802154/ieee802154_sendto.c b/net/ieee802154/ieee802154_sendto.c
index cd00576b86..b251213b9e 100644
--- a/net/ieee802154/ieee802154_sendto.c
+++ b/net/ieee802154/ieee802154_sendto.c
@@ -487,7 +487,7 @@ ssize_t psock_ieee802154_sendto(FAR struct socket *psock, FAR const void *buf,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.is_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&state.is_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&state.is_sem, SEM_PRIO_NONE);
 
   state.is_sock   = psock;          /* Socket descriptor to use */
diff --git a/net/igmp/igmp_group.c b/net/igmp/igmp_group.c
index 74039fb578..c61e83f6ec 100644
--- a/net/igmp/igmp_group.c
+++ b/net/igmp/igmp_group.c
@@ -135,7 +135,7 @@ FAR struct igmp_group_s *igmp_grpalloc(FAR struct net_driver_s *dev,
        * priority inheritance enabled.
        */
 
-      sem_init(&group->sem, 0, 0);
+      nxsem_init(&group->sem, 0, 0);
       sem_setprotocol(&group->sem, SEM_PRIO_NONE);
 
       /* Initialize the group timer (but don't start it yet) */
diff --git a/net/inet/inet_close.c b/net/inet/inet_close.c
index 12f6b44896..f69db30d2e 100644
--- a/net/inet/inet_close.c
+++ b/net/inet/inet_close.c
@@ -388,7 +388,7 @@ static inline int tcp_close_disconnect(FAR struct socket *psock)
            * priority inheritance enabled.
            */
 
-          sem_init(&state.cl_sem, 0, 0);
+          nxsem_init(&state.cl_sem, 0, 0);
           sem_setprotocol(&state.cl_sem, SEM_PRIO_NONE);
 
           /* Record the time that we started the wait (in ticks) */
diff --git a/net/inet/inet_recvfrom.c b/net/inet/inet_recvfrom.c
index 7035d71a5f..bcba9124d3 100644
--- a/net/inet/inet_recvfrom.c
+++ b/net/inet/inet_recvfrom.c
@@ -1087,7 +1087,7 @@ static void inet_recvfrom_initialize(FAR struct socket *psock, FAR void *buf,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&pstate->ir_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&pstate->ir_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&pstate->ir_sem, SEM_PRIO_NONE);
 
   pstate->ir_buflen    = len;
diff --git a/net/local/local_conn.c b/net/local/local_conn.c
index e70f8df7ab..e1e7ba0af7 100644
--- a/net/local/local_conn.c
+++ b/net/local/local_conn.c
@@ -99,7 +99,7 @@ FAR struct local_conn_s *local_alloc(void)
        * priority inheritance enabled.
        */
 
-      sem_init(&conn->lc_waitsem, 0, 0);
+      nxsem_init(&conn->lc_waitsem, 0, 0);
       sem_setprotocol(&conn->lc_waitsem, SEM_PRIO_NONE);
 
 #ifdef HAVE_LOCAL_POLL
diff --git a/net/local/local_connect.c b/net/local/local_connect.c
index 99e28ff8dc..3044551707 100644
--- a/net/local/local_connect.c
+++ b/net/local/local_connect.c
@@ -184,7 +184,7 @@ static int inline local_stream_connect(FAR struct local_conn_s *client,
   client->lc_state = LOCAL_STATE_ACCEPT;
   local_accept_pollnotify(server, POLLIN);
 
-  if (sem_getvalue(&server->lc_waitsem, &sval) >= 0 && sval < 1)
+  if (nxsem_getvalue(&server->lc_waitsem, &sval) >= 0 && sval < 1)
     {
       _local_semgive(&server->lc_waitsem);
     }
diff --git a/net/pkt/pkt_conn.c b/net/pkt/pkt_conn.c
index cc4954a1ec..55e6ffa9c7 100644
--- a/net/pkt/pkt_conn.c
+++ b/net/pkt/pkt_conn.c
@@ -128,7 +128,7 @@ void pkt_initialize(void)
 
   dq_init(&g_free_pkt_connections);
   dq_init(&g_active_pkt_connections);
-  sem_init(&g_free_sem, 0, 1);
+  nxsem_init(&g_free_sem, 0, 1);
 
   for (i = 0; i < CONFIG_NET_PKT_CONNS; i++)
     {
diff --git a/net/pkt/pkt_recvfrom.c b/net/pkt/pkt_recvfrom.c
index bb5523c349..8f612a0368 100644
--- a/net/pkt/pkt_recvfrom.c
+++ b/net/pkt/pkt_recvfrom.c
@@ -264,7 +264,7 @@ static void pkt_recvfrom_initialize(FAR struct socket *psock, FAR void *buf,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&pstate->pr_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&pstate->pr_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&pstate->pr_sem, SEM_PRIO_NONE);
 
   pstate->pr_buflen = len;
diff --git a/net/pkt/pkt_send.c b/net/pkt/pkt_send.c
index f2197ac340..e979296fb7 100644
--- a/net/pkt/pkt_send.c
+++ b/net/pkt/pkt_send.c
@@ -209,7 +209,7 @@ ssize_t psock_pkt_send(FAR struct socket *psock, FAR const void *buf,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   state.snd_sock      = psock;          /* Socket descriptor to use */
diff --git a/net/route/net_cacheroute.c b/net/route/net_cacheroute.c
index 6dcd17bdbe..4c62435148 100644
--- a/net/route/net_cacheroute.c
+++ b/net/route/net_cacheroute.c
@@ -517,12 +517,12 @@ void net_init_cacheroute(void)
   /* Initialize the routing table cash and the free list */
 
 #ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
-  sem_init(&g_ipv4_cachelock, 0, 1);
+  nxsem_init(&g_ipv4_cachelock, 0, 1);
   net_reset_ipv4_cache();
 #endif
 
 #ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
-  sem_init(&g_ipv6_cachelock, 0, 1);
+  nxsem_init(&g_ipv6_cachelock, 0, 1);
   net_reset_ipv6_cache();
 #endif
 }
diff --git a/net/route/net_fileroute.c b/net/route/net_fileroute.c
index 3865916749..bc3b7ab2cd 100644
--- a/net/route/net_fileroute.c
+++ b/net/route/net_fileroute.c
@@ -233,11 +233,11 @@ void net_init_fileroute(void)
   /* Initialize semaphores */
 
 #ifdef CONFIG_ROUTE_IPv4_FILEROUTE
-  sem_init(&g_ipv4_exclsem, 0, 1);
+  nxsem_init(&g_ipv4_exclsem, 0, 1);
 #endif
 
 #ifdef CONFIG_ROUTE_IPv6_FILEROUTE
-  sem_init(&g_ipv6_exclsem, 0, 1);
+  nxsem_init(&g_ipv6_exclsem, 0, 1);
 #endif
 }
 
diff --git a/net/sixlowpan/sixlowpan_send.c b/net/sixlowpan/sixlowpan_send.c
index 3fe52d0743..01dbc02c30 100644
--- a/net/sixlowpan/sixlowpan_send.c
+++ b/net/sixlowpan/sixlowpan_send.c
@@ -281,7 +281,7 @@ int sixlowpan_send(FAR struct net_driver_s *dev,
 
   /* Initialize the send state structure */
 
-  sem_init(&sinfo.s_waitsem, 0, 0);
+  nxsem_init(&sinfo.s_waitsem, 0, 0);
   (void)sem_setprotocol(&sinfo.s_waitsem, SEM_PRIO_NONE);
 
   sinfo.s_result  = -EBUSY;
diff --git a/net/sixlowpan/sixlowpan_tcpsend.c b/net/sixlowpan/sixlowpan_tcpsend.c
index 612031a81d..115e60f262 100644
--- a/net/sixlowpan/sixlowpan_tcpsend.c
+++ b/net/sixlowpan/sixlowpan_tcpsend.c
@@ -662,7 +662,7 @@ static int sixlowpan_send_packet(FAR struct socket *psock,
 
           /* Initialize the send state structure */
 
-          sem_init(&sinfo.s_waitsem, 0, 0);
+          nxsem_init(&sinfo.s_waitsem, 0, 0);
           (void)sem_setprotocol(&sinfo.s_waitsem, SEM_PRIO_NONE);
 
           sinfo.s_sock      = psock;
diff --git a/net/socket/net_sockets.c b/net/socket/net_sockets.c
index a614af3bdc..2403b7d09a 100644
--- a/net/socket/net_sockets.c
+++ b/net/socket/net_sockets.c
@@ -99,7 +99,7 @@ void net_initlist(FAR struct socketlist *list)
 {
   /* Initialize the list access mutex */
 
-  (void)sem_init(&list->sl_sem, 0, 1);
+  (void)nxsem_init(&list->sl_sem, 0, 1);
 }
 
 /****************************************************************************
diff --git a/net/tcp/tcp_accept.c b/net/tcp/tcp_accept.c
index 45fd7c1309..8c3572fb3c 100644
--- a/net/tcp/tcp_accept.c
+++ b/net/tcp/tcp_accept.c
@@ -285,7 +285,7 @@ int psock_tcp_accept(FAR struct socket *psock, FAR struct sockaddr *addr,
        * priority inheritance enabled.
        */
 
-      sem_init(&state.acpt_sem, 0, 0);
+      nxsem_init(&state.acpt_sem, 0, 0);
       sem_setprotocol(&state.acpt_sem, SEM_PRIO_NONE);
 
       /* Set up the callback in the connection */
diff --git a/net/tcp/tcp_connect.c b/net/tcp/tcp_connect.c
index 80317d4427..2eeaf7cb4c 100644
--- a/net/tcp/tcp_connect.c
+++ b/net/tcp/tcp_connect.c
@@ -106,7 +106,7 @@ static inline int psock_setup_callbacks(FAR struct socket *psock,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&pstate->tc_sem, 0, 0); /* Doesn't really fail */
+  (void)nxsem_init(&pstate->tc_sem, 0, 0); /* Doesn't really fail */
   (void)sem_setprotocol(&pstate->tc_sem, SEM_PRIO_NONE);
 
   pstate->tc_conn   = conn;
diff --git a/net/tcp/tcp_send_unbuffered.c b/net/tcp/tcp_send_unbuffered.c
index e9d687c75a..faa713f2e1 100644
--- a/net/tcp/tcp_send_unbuffered.c
+++ b/net/tcp/tcp_send_unbuffered.c
@@ -792,7 +792,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock,
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&state.snd_sem, 0, 0);    /* Doesn't really fail */
+  (void)nxsem_init(&state.snd_sem, 0, 0);    /* Doesn't really fail */
   (void)sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   state.snd_sock      = psock;             /* Socket descriptor to use */
diff --git a/net/tcp/tcp_sendfile.c b/net/tcp/tcp_sendfile.c
index ae48e2284a..fa00769b4c 100644
--- a/net/tcp/tcp_sendfile.c
+++ b/net/tcp/tcp_sendfile.c
@@ -619,7 +619,7 @@ ssize_t tcp_sendfile(FAR struct socket *psock, FAR struct file *infile,
    * priority inheritance enabled.
    */
 
-  sem_init(&state.snd_sem, 0, 0);           /* Doesn't really fail */
+  nxsem_init(&state.snd_sem, 0, 0);           /* Doesn't really fail */
   sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
 
   state.snd_sock    = psock;                /* Socket descriptor to use */
diff --git a/net/tcp/tcp_wrbuffer.c b/net/tcp/tcp_wrbuffer.c
index 29fba3ddce..a8da18091e 100644
--- a/net/tcp/tcp_wrbuffer.c
+++ b/net/tcp/tcp_wrbuffer.c
@@ -114,7 +114,7 @@ void tcp_wrbuffer_initialize(void)
       sq_addfirst(&g_wrbuffer.buffers[i].wb_node, &g_wrbuffer.freebuffers);
     }
 
-  sem_init(&g_wrbuffer.sem, 0, CONFIG_NET_TCP_NWRBCHAINS);
+  nxsem_init(&g_wrbuffer.sem, 0, CONFIG_NET_TCP_NWRBCHAINS);
 }
 
 /****************************************************************************
@@ -211,7 +211,7 @@ void tcp_wrbuffer_release(FAR struct tcp_wrbuffer_s *wrb)
 int tcp_wrbuffer_test(void)
 {
   int val = 0;
-  sem_getvalue(&g_wrbuffer.sem, &val);
+  nxsem_getvalue(&g_wrbuffer.sem, &val);
   return val > 0 ? OK : ERROR;
 }
 
diff --git a/net/udp/udp_conn.c b/net/udp/udp_conn.c
index 210ce351e0..c6a85dfa96 100644
--- a/net/udp/udp_conn.c
+++ b/net/udp/udp_conn.c
@@ -445,7 +445,7 @@ void udp_initialize(void)
 
   dq_init(&g_free_udp_connections);
   dq_init(&g_active_udp_connections);
-  sem_init(&g_free_sem, 0, 1);
+  nxsem_init(&g_free_sem, 0, 1);
 
   for (i = 0; i < CONFIG_NET_UDP_CONNS; i++)
     {
diff --git a/net/udp/udp_psock_sendto.c b/net/udp/udp_psock_sendto.c
index 4a8eb83b2a..6ba4055975 100644
--- a/net/udp/udp_psock_sendto.c
+++ b/net/udp/udp_psock_sendto.c
@@ -397,7 +397,7 @@ ssize_t psock_udp_sendto(FAR struct socket *psock, FAR const void *buf,
    * priority inheritance enabled.
    */
 
-  sem_init(&state.st_sem, 0, 0);
+  nxsem_init(&state.st_sem, 0, 0);
   sem_setprotocol(&state.st_sem, SEM_PRIO_NONE);
 
   state.st_buflen = len;
diff --git a/net/usrsock/usrsock_conn.c b/net/usrsock/usrsock_conn.c
index b22762b3d5..5ea9db9c36 100644
--- a/net/usrsock/usrsock_conn.c
+++ b/net/usrsock/usrsock_conn.c
@@ -256,7 +256,7 @@ int usrsock_setup_request_callback(FAR struct usrsock_conn_s *conn,
 {
   int ret = -EBUSY;
 
-  (void)sem_init(&pstate->recvsem, 0, 0);
+  (void)nxsem_init(&pstate->recvsem, 0, 0);
   pstate->conn   = conn;
   pstate->result = -EAGAIN;
   pstate->completed = false;
@@ -324,7 +324,7 @@ void usrsock_initialize(void)
 
   dq_init(&g_free_usrsock_connections);
   dq_init(&g_active_usrsock_connections);
-  sem_init(&g_free_sem, 0, 1);
+  nxsem_init(&g_free_sem, 0, 1);
 
   for (i = 0; i < CONFIG_NET_USRSOCK_CONNS; i++)
     {
diff --git a/net/usrsock/usrsock_dev.c b/net/usrsock/usrsock_dev.c
index 0bf4a949d4..ca6b5f2160 100644
--- a/net/usrsock/usrsock_dev.c
+++ b/net/usrsock/usrsock_dev.c
@@ -1260,9 +1260,9 @@ void usrsockdev_register(void)
 
   g_usrsockdev.ocount = 0;
   g_usrsockdev.req.nbusy = 0;
-  sem_init(&g_usrsockdev.devsem, 0, 1);
-  sem_init(&g_usrsockdev.req.sem, 0, 1);
-  sem_init(&g_usrsockdev.req.acksem, 0, 0);
+  nxsem_init(&g_usrsockdev.devsem, 0, 1);
+  nxsem_init(&g_usrsockdev.req.sem, 0, 1);
+  nxsem_init(&g_usrsockdev.req.acksem, 0, 0);
 
   (void)register_driver("/dev/usrsock", &g_usrsockdevops, 0666, &g_usrsockdev);
 }
diff --git a/net/utils/net_lock.c b/net/utils/net_lock.c
index 482933238e..47701a3ec7 100644
--- a/net/utils/net_lock.c
+++ b/net/utils/net_lock.c
@@ -104,7 +104,7 @@ static void _net_takesem(void)
 
 void net_lockinitialize(void)
 {
-  sem_init(&g_netlock, 0, 1);
+  nxsem_init(&g_netlock, 0, 1);
 }
 
 /****************************************************************************
diff --git a/sched/group/group_create.c b/sched/group/group_create.c
index b3c36a1a02..d35b4a55d4 100644
--- a/sched/group/group_create.c
+++ b/sched/group/group_create.c
@@ -245,7 +245,7 @@ int group_allocate(FAR struct task_tcb_s *tcb, uint8_t ttype)
 #ifndef CONFIG_DISABLE_PTHREAD
   /* Initialize the pthread join semaphore */
 
-  (void)sem_init(&group->tg_joinsem, 0, 1);
+  (void)nxsem_init(&group->tg_joinsem, 0, 1);
 #endif
 
 #if defined(CONFIG_SCHED_WAITPID) && !defined(CONFIG_SCHED_HAVE_PARENT)
@@ -255,7 +255,7 @@ int group_allocate(FAR struct task_tcb_s *tcb, uint8_t ttype)
    * priority inheritance enabled.
    */
 
-  (void)sem_init(&group->tg_exitsem, 0, 0);
+  (void)nxsem_init(&group->tg_exitsem, 0, 0);
   (void)sem_setprotocol(&group->tg_exitsem, SEM_PRIO_NONE);
 #endif
 
diff --git a/sched/init/os_start.c b/sched/init/os_start.c
index ab129440e4..5f64f4d937 100644
--- a/sched/init/os_start.c
+++ b/sched/init/os_start.c
@@ -543,7 +543,7 @@ void os_start(void)
    * because many subsystems depend upon fully functional semaphores.
    */
 
-  sem_initialize();
+  nxsem_initialize();
 
 #if defined(MM_KERNEL_USRHEAP_INIT) || defined(CONFIG_MM_KERNEL_HEAP) || \
     defined(CONFIG_MM_PGALLOC)
diff --git a/sched/pthread/pthread_completejoin.c b/sched/pthread/pthread_completejoin.c
index c8ef85c5d4..d355719d36 100644
--- a/sched/pthread/pthread_completejoin.c
+++ b/sched/pthread/pthread_completejoin.c
@@ -72,14 +72,14 @@ static bool pthread_notifywaiters(FAR struct join_s *pjoin)
 
   /* Are any tasks waiting for our exit value? */
 
-  status = sem_getvalue(&pjoin->exit_sem, &ntasks_waiting);
+  status = nxsem_getvalue(&pjoin->exit_sem, &ntasks_waiting);
   if (status == OK && ntasks_waiting < 0)
     {
       /* Set the data semaphore so that this thread will be
        * awakened when all waiting tasks receive the data
        */
 
-      (void)sem_init(&pjoin->data_sem, 0, (ntasks_waiting + 1));
+      (void)nxsem_init(&pjoin->data_sem, 0, (ntasks_waiting + 1));
 
       /* Post the semaphore to restart each thread that is waiting
        * on the semaphore
@@ -90,7 +90,7 @@ static bool pthread_notifywaiters(FAR struct join_s *pjoin)
           status = pthread_sem_give(&pjoin->exit_sem);
           if (status == OK)
             {
-              status = sem_getvalue(&pjoin->exit_sem, &ntasks_waiting);
+              status = nxsem_getvalue(&pjoin->exit_sem, &ntasks_waiting);
             }
         }
       while (ntasks_waiting < 0 && status == OK);
diff --git a/sched/pthread/pthread_condbroadcast.c b/sched/pthread/pthread_condbroadcast.c
index de637c9e1e..0fddd76927 100644
--- a/sched/pthread/pthread_condbroadcast.c
+++ b/sched/pthread/pthread_condbroadcast.c
@@ -88,7 +88,7 @@ int pthread_cond_broadcast(FAR pthread_cond_t *cond)
 
       /* Get the current value of the semaphore */
 
-      if (sem_getvalue((FAR sem_t *)&cond->sem, &sval) != OK)
+      if (nxsem_getvalue((FAR sem_t *)&cond->sem, &sval) != OK)
         {
           ret = EINVAL;
         }
diff --git a/sched/pthread/pthread_condsignal.c b/sched/pthread/pthread_condsignal.c
index e5f9af31af..5826a425de 100644
--- a/sched/pthread/pthread_condsignal.c
+++ b/sched/pthread/pthread_condsignal.c
@@ -80,7 +80,7 @@ int pthread_cond_signal(FAR pthread_cond_t *cond)
     {
       /* Get the current value of the semaphore */
 
-      if (sem_getvalue((FAR sem_t *)&cond->sem, &sval) != OK)
+      if (nxsem_getvalue((FAR sem_t *)&cond->sem, &sval) != OK)
         {
           ret = EINVAL;
         }
diff --git a/sched/pthread/pthread_create.c b/sched/pthread/pthread_create.c
index 4cde28f789..9d2fcf5080 100644
--- a/sched/pthread/pthread_create.c
+++ b/sched/pthread/pthread_create.c
@@ -501,10 +501,15 @@ int pthread_create(FAR pthread_t *thread, FAR const pthread_attr_t *attr,
 
   /* Initialize the semaphores in the join structure to zero. */
 
-  ret = sem_init(&pjoin->data_sem, 0, 0);
+  ret = nxsem_init(&pjoin->data_sem, 0, 0);
   if (ret == OK)
     {
-      ret = sem_init(&pjoin->exit_sem, 0, 0);
+      ret = nxsem_init(&pjoin->exit_sem, 0, 0);
+    }
+
+  if (ret < 0)
+    {
+      ret = -ret;
     }
 
   /* Thse semaphores are used for signaling and, hence, should not have
@@ -514,11 +519,16 @@ int pthread_create(FAR pthread_t *thread, FAR const pthread_attr_t *attr,
   if (ret == OK)
     {
       ret = sem_setprotocol(&pjoin->data_sem, SEM_PRIO_NONE);
-    }
 
-  if (ret == OK)
-    {
-      ret = sem_setprotocol(&pjoin->exit_sem, SEM_PRIO_NONE);
+      if (ret == OK)
+        {
+          ret = sem_setprotocol(&pjoin->exit_sem, SEM_PRIO_NONE);
+        }
+
+      if (ret < 0)
+        {
+          ret = get_errno();
+        }
     }
 
   /* If the priority of the new pthread is lower than the priority of the
@@ -538,6 +548,10 @@ int pthread_create(FAR pthread_t *thread, FAR const pthread_attr_t *attr,
       if (ptcb->cmn.sched_priority < parent->sched_priority)
         {
           ret = sched_setpriority(&ptcb->cmn, parent->sched_priority);
+          if (ret < 0)
+            {
+              ret = get_errno();
+            }
         }
     }
 
@@ -547,6 +561,10 @@ int pthread_create(FAR pthread_t *thread, FAR const pthread_attr_t *attr,
   if (ret == OK)
     {
       ret = task_activate((FAR struct tcb_s *)ptcb);
+      if (ret < 0)
+        {
+          ret = get_errno();
+        }
     }
 
   if (ret == OK)
diff --git a/sched/pthread/pthread_mutexconsistent.c b/sched/pthread/pthread_mutexconsistent.c
index dac4fcf043..c00331d1f9 100644
--- a/sched/pthread/pthread_mutexconsistent.c
+++ b/sched/pthread/pthread_mutexconsistent.c
@@ -128,7 +128,7 @@ int pthread_mutex_consistent(FAR pthread_mutex_t *mutex)
                * dead task had called pthread_mutex_unlock().
                */
 
-              status = sem_reset((FAR sem_t *)&mutex->sem, 1);
+              status = nxsem_reset((FAR sem_t *)&mutex->sem, 1);
               ret = (status != OK) ? get_errno() : OK;
             }
 
diff --git a/sched/pthread/pthread_mutexdestroy.c b/sched/pthread/pthread_mutexdestroy.c
index 23905fd407..f1a91853b7 100644
--- a/sched/pthread/pthread_mutexdestroy.c
+++ b/sched/pthread/pthread_mutexdestroy.c
@@ -112,7 +112,7 @@ int pthread_mutex_destroy(FAR pthread_mutex_t *mutex)
                * destruction of the semaphore impossible here.
                */
 
-              status = sem_reset((FAR sem_t *)&mutex->sem, 1);
+              status = nxsem_reset((FAR sem_t *)&mutex->sem, 1);
               if (status < 0)
                 {
                   ret = -status;
@@ -147,7 +147,7 @@ int pthread_mutex_destroy(FAR pthread_mutex_t *mutex)
           /* Destroy the semaphore
            *
            * REVISIT:  What if there are threads waiting on the semaphore?
-           * Perhaps this logic should all sem_reset() first?
+           * Perhaps this logic should all nxsem_reset() first?
            */
 
           status = sem_destroy((FAR sem_t *)&mutex->sem);
diff --git a/sched/pthread/pthread_mutexinit.c b/sched/pthread/pthread_mutexinit.c
index ec84fef609..69fa05eb47 100644
--- a/sched/pthread/pthread_mutexinit.c
+++ b/sched/pthread/pthread_mutexinit.c
@@ -118,7 +118,7 @@ int pthread_mutex_init(FAR pthread_mutex_t *mutex,
 
       /* Initialize the mutex like a semaphore with initial count = 1 */
 
-      status = sem_init((FAR sem_t *)&mutex->sem, pshared, 1);
+      status = nxsem_init((FAR sem_t *)&mutex->sem, pshared, 1);
       if (status != OK)
         {
           ret = get_errno();
diff --git a/sched/semaphore/sem_destroy.c b/sched/semaphore/sem_destroy.c
index 7518382bb9..706112e782 100644
--- a/sched/semaphore/sem_destroy.c
+++ b/sched/semaphore/sem_destroy.c
@@ -53,11 +53,11 @@
  *
  * Description:
  *   This function is used to destroy the un-named semaphore indicated by
- *   'sem'.  Only a semaphore that was created using sem_init() may be
+ *   'sem'.  Only a semaphore that was created using nxsem_init() may be
  *   destroyed using sem_destroy(); the effect of calling sem_destroy() with
  *   a named semaphore is undefined.  The effect of subsequent use of the
  *   semaphore sem is undefined until sem is re-initialized by another call
- *   to sem_init().
+ *   to nxsem_init().
  *
  *   The effect of destroying a semaphore upon which other processes are
  *   currently blocked is undefined.
@@ -95,7 +95,7 @@ int sem_destroy (FAR sem_t *sem)
 
       /* Release holders of the semaphore */
 
-      sem_destroyholder(sem);
+      nxsem_destroyholder(sem);
       return OK;
     }
   else
diff --git a/sched/semaphore/sem_holder.c b/sched/semaphore/sem_holder.c
index 7046ab756a..dca9e98b78 100644
--- a/sched/semaphore/sem_holder.c
+++ b/sched/semaphore/sem_holder.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * sched/semaphore/sem_holder.c
  *
- *   Copyright (C) 2009-2011, 2013, 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2011, 2013, 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -79,10 +79,10 @@ static FAR struct semholder_s *g_freeholders;
 #endif
 
 /****************************************************************************
- * Name: sem_allocholder
+ * Name: nxsem_allocholder
  ****************************************************************************/
 
-static inline FAR struct semholder_s *sem_allocholder(sem_t *sem)
+static inline FAR struct semholder_s *nxsem_allocholder(sem_t *sem)
 {
   FAR struct semholder_s *pholder;
 
@@ -130,11 +130,11 @@ static inline FAR struct semholder_s *sem_allocholder(sem_t *sem)
 }
 
 /****************************************************************************
- * Name: sem_findholder
+ * Name: nxsem_findholder
  ****************************************************************************/
 
-static FAR struct semholder_s *sem_findholder(sem_t *sem,
-                                              FAR struct tcb_s *htcb)
+static FAR struct semholder_s *nxsem_findholder(sem_t *sem,
+                                                FAR struct tcb_s *htcb)
 {
   FAR struct semholder_s *pholder;
 
@@ -176,26 +176,27 @@ static FAR struct semholder_s *sem_findholder(sem_t *sem,
 }
 
 /****************************************************************************
- * Name: sem_findorallocateholder
+ * Name: nxsem_findorallocateholder
  ****************************************************************************/
 
 static inline FAR struct semholder_s *
-sem_findorallocateholder(sem_t *sem, FAR struct tcb_s *htcb)
+nxsem_findorallocateholder(sem_t *sem, FAR struct tcb_s *htcb)
 {
-  FAR struct semholder_s *pholder = sem_findholder(sem, htcb);
+  FAR struct semholder_s *pholder = nxsem_findholder(sem, htcb);
   if (!pholder)
     {
-      pholder = sem_allocholder(sem);
+      pholder = nxsem_allocholder(sem);
     }
 
   return pholder;
 }
 
 /****************************************************************************
- * Name: sem_freeholder
+ * Name: nxsem_freeholder
  ****************************************************************************/
 
-static inline void sem_freeholder(sem_t *sem, FAR struct semholder_s *pholder)
+static inline void nxsem_freeholder(sem_t *sem,
+                                    FAR struct semholder_s *pholder)
 {
 #if CONFIG_SEM_PREALLOCHOLDERS > 0
   FAR struct semholder_s *curr;
@@ -236,29 +237,29 @@ static inline void sem_freeholder(sem_t *sem, FAR struct semholder_s *pholder)
 }
 
 /****************************************************************************
- * Name: sem_findandfreeholder
+ * Name: nxsem_findandfreeholder
  ****************************************************************************/
 
-static inline void sem_findandfreeholder(sem_t *sem, FAR struct tcb_s *htcb)
+static inline void nxsem_findandfreeholder(sem_t *sem, FAR struct tcb_s *htcb)
 {
-  FAR struct semholder_s *pholder = sem_findholder(sem, htcb);
+  FAR struct semholder_s *pholder = nxsem_findholder(sem, htcb);
 
   /* When no more counts are held, remove the holder from the list.  The
-   * count was decremented in sem_releaseholder.
+   * count was decremented in nxsem_releaseholder.
    */
 
   if (pholder != NULL && pholder->counts <= 0)
     {
-      sem_freeholder(sem, pholder);
+      nxsem_freeholder(sem, pholder);
     }
 }
 
 /****************************************************************************
- * Name: sem_foreachholder
+ * Name: nxsem_foreachholder
  ****************************************************************************/
 
-static int sem_foreachholder(FAR sem_t *sem, holderhandler_t handler,
-                             FAR void *arg)
+static int nxsem_foreachholder(FAR sem_t *sem, holderhandler_t handler,
+                               FAR void *arg)
 {
   FAR struct semholder_s *pholder;
   int ret = 0;
@@ -307,24 +308,24 @@ static int sem_foreachholder(FAR sem_t *sem, holderhandler_t handler,
 }
 
 /****************************************************************************
- * Name: sem_recoverholders
+ * Name: nxsem_recoverholders
  ****************************************************************************/
 
 #if CONFIG_SEM_PREALLOCHOLDERS > 0
-static int sem_recoverholders(FAR struct semholder_s *pholder,
-                              FAR sem_t *sem, FAR void *arg)
+static int nxsem_recoverholders(FAR struct semholder_s *pholder,
+                                FAR sem_t *sem, FAR void *arg)
 {
-  sem_freeholder(sem, pholder);
+  nxsem_freeholder(sem, pholder);
   return 0;
 }
 #endif
 
 /****************************************************************************
- * Name: sem_boostholderprio
+ * Name: nxsem_boostholderprio
  ****************************************************************************/
 
-static int sem_boostholderprio(FAR struct semholder_s *pholder,
-                               FAR sem_t *sem, FAR void *arg)
+static int nxsem_boostholderprio(FAR struct semholder_s *pholder,
+                                 FAR sem_t *sem, FAR void *arg)
 {
   FAR struct tcb_s *htcb = (FAR struct tcb_s *)pholder->htcb;
   FAR struct tcb_s *rtcb = (FAR struct tcb_s *)arg;
@@ -339,7 +340,7 @@ static int sem_boostholderprio(FAR struct semholder_s *pholder,
     {
       serr("ERROR: TCB 0x%08x is a stale handle, counts lost\n", htcb);
       DEBUGPANIC();
-      sem_freeholder(sem, pholder);
+      nxsem_freeholder(sem, pholder);
     }
 
 #if CONFIG_SEM_NNESTPRIO > 0
@@ -432,12 +433,12 @@ static int sem_boostholderprio(FAR struct semholder_s *pholder,
 }
 
 /****************************************************************************
- * Name: sem_verifyholder
+ * Name: nxsem_verifyholder
  ****************************************************************************/
 
 #ifdef CONFIG_DEBUG_ASSERTIONS
-static int sem_verifyholder(FAR struct semholder_s *pholder, FAR sem_t *sem,
-                            FAR void *arg)
+static int nxsem_verifyholder(FAR struct semholder_s *pholder,
+                              FAR sem_t *sem, FAR void *arg)
 {
 #if 0 /* Need to revisit this, but these assumptions seem to be untrue -- \
        * OR there is a bug??? */
@@ -458,12 +459,12 @@ static int sem_verifyholder(FAR struct semholder_s *pholder, FAR sem_t *sem,
 #endif
 
 /****************************************************************************
- * Name: sem_dumpholder
+ * Name: nxsem_dumpholder
  ****************************************************************************/
 
 #if defined(CONFIG_DEBUG_INFO) && defined(CONFIG_SEM_PHDEBUG)
-static int sem_dumpholder(FAR struct semholder_s *pholder, FAR sem_t *sem,
-                          FAR void *arg)
+static int nxsem_dumpholder(FAR struct semholder_s *pholder, FAR sem_t *sem,
+                            FAR void *arg)
 {
 #if CONFIG_SEM_PREALLOCHOLDERS > 0
   _info("  %08x: %08x %08x %04x\n",
@@ -476,11 +477,11 @@ static int sem_dumpholder(FAR struct semholder_s *pholder, FAR sem_t *sem,
 #endif
 
 /****************************************************************************
- * Name: sem_restoreholderprio
+ * Name: nxsem_restoreholderprio
  ****************************************************************************/
 
-static int sem_restoreholderprio(FAR struct tcb_s *htcb,
-                                 FAR sem_t *sem, FAR void *arg)
+static int nxsem_restoreholderprio(FAR struct tcb_s *htcb,
+                                   FAR sem_t *sem, FAR void *arg)
 {
   FAR struct semholder_s *pholder = 0;
 #if CONFIG_SEM_NNESTPRIO > 0
@@ -500,10 +501,10 @@ static int sem_restoreholderprio(FAR struct tcb_s *htcb,
     {
       serr("ERROR: TCB 0x%08x is a stale handle, counts lost\n", htcb);
       DEBUGPANIC();
-      pholder = sem_findholder(sem, htcb);
+      pholder = nxsem_findholder(sem, htcb);
       if (pholder != NULL)
         {
-          sem_freeholder(sem, pholder);
+          nxsem_freeholder(sem, pholder);
         }
     }
 
@@ -624,49 +625,49 @@ static int sem_restoreholderprio(FAR struct tcb_s *htcb,
 }
 
 /****************************************************************************
- * Name: sem_restoreholderprioall
+ * Name: nxsem_restoreholderprioall
  *
  * Description:
  *   Reprioritize all holders
  *
  ****************************************************************************/
 
-static int sem_restoreholderprioall(FAR struct semholder_s *pholder,
-                                    FAR sem_t *sem, FAR void *arg)
+static int nxsem_restoreholderprioall(FAR struct semholder_s *pholder,
+                                      FAR sem_t *sem, FAR void *arg)
 {
-  return sem_restoreholderprio(pholder->htcb, sem, arg);
+  return nxsem_restoreholderprio(pholder->htcb, sem, arg);
 }
 
 /****************************************************************************
- * Name: sem_restoreholderprioA
+ * Name: nxsem_restoreholderprioA
  *
  * Description:
  *   Reprioritize all holders except the currently executing task
  *
  ****************************************************************************/
 
-static int sem_restoreholderprioA(FAR struct semholder_s *pholder,
-                                  FAR sem_t *sem, FAR void *arg)
+static int nxsem_restoreholderprioA(FAR struct semholder_s *pholder,
+                                    FAR sem_t *sem, FAR void *arg)
 {
   FAR struct tcb_s *rtcb = this_task();
   if (pholder->htcb != rtcb)
     {
-      return sem_restoreholderprio(pholder->htcb, sem, arg);
+      return nxsem_restoreholderprio(pholder->htcb, sem, arg);
     }
 
   return 0;
 }
 
 /****************************************************************************
- * Name: sem_restoreholderprioB
+ * Name: nxsem_restoreholderprioB
  *
  * Description:
  *   Reprioritize only the currently executing task
  *
  ****************************************************************************/
 
-static int sem_restoreholderprioB(FAR struct semholder_s *pholder,
-                                  FAR sem_t *sem, FAR void *arg)
+static int nxsem_restoreholderprioB(FAR struct semholder_s *pholder,
+                                    FAR sem_t *sem, FAR void *arg)
 {
   FAR struct tcb_s *rtcb = this_task();
 
@@ -682,9 +683,9 @@ static int sem_restoreholderprioB(FAR struct semholder_s *pholder,
        * causes a context switch.
        */
 
-      sem_findandfreeholder(sem, rtcb);
+      nxsem_findandfreeholder(sem, rtcb);
 #endif
-      (void)sem_restoreholderprio(rtcb, sem, arg);
+      (void)nxsem_restoreholderprio(rtcb, sem, arg);
       return 1;
     }
 
@@ -692,7 +693,7 @@ static int sem_restoreholderprioB(FAR struct semholder_s *pholder,
 }
 
 /****************************************************************************
- * Name: sem_restorebaseprio_irq
+ * Name: nxsem_restorebaseprio_irq
  *
  * Description:
  *   This function is called after the an interrupt handler posts a count on
@@ -723,8 +724,8 @@ static int sem_restoreholderprioB(FAR struct semholder_s *pholder,
  *
  ****************************************************************************/
 
-static inline void sem_restorebaseprio_irq(FAR struct tcb_s *stcb,
-                                           FAR sem_t *sem)
+static inline void nxsem_restorebaseprio_irq(FAR struct tcb_s *stcb,
+                                             FAR sem_t *sem)
 {
   /* Perform the following actions only if a new thread was given a count.
    * The thread that received the count should be the highest priority
@@ -737,7 +738,7 @@ static inline void sem_restorebaseprio_irq(FAR struct tcb_s *stcb,
     {
       /* Drop the priority of all holder threads */
 
-      (void)sem_foreachholder(sem, sem_restoreholderprioall, stcb);
+      (void)nxsem_foreachholder(sem, nxsem_restoreholderprioall, stcb);
     }
 
   /* If there are no tasks waiting for available counts, then all holders
@@ -747,13 +748,13 @@ static inline void sem_restorebaseprio_irq(FAR struct tcb_s *stcb,
 #ifdef CONFIG_DEBUG_ASSERTIONS
   else
     {
-      (void)sem_foreachholder(sem, sem_verifyholder, NULL);
+      (void)nxsem_foreachholder(sem, nxsem_verifyholder, NULL);
     }
 #endif
 }
 
 /****************************************************************************
- * Name: sem_restorebaseprio_task
+ * Name: nxsem_restorebaseprio_task
  *
  * Description:
  *   This function is called after the current running task releases a
@@ -784,8 +785,8 @@ static inline void sem_restorebaseprio_irq(FAR struct tcb_s *stcb,
  *
  ****************************************************************************/
 
-static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
-                                            FAR sem_t *sem)
+static inline void nxsem_restorebaseprio_task(FAR struct tcb_s *stcb,
+                                              FAR sem_t *sem)
 {
   FAR struct tcb_s *rtcb = this_task();
 
@@ -807,11 +808,11 @@ static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
        * except for the running thread.
        */
 
-      (void)sem_foreachholder(sem, sem_restoreholderprioA, stcb);
+      (void)nxsem_foreachholder(sem, nxsem_restoreholderprioA, stcb);
 
       /* Now, find an reprioritize only the ready to run task */
 
-      (void)sem_foreachholder(sem, sem_restoreholderprioB, stcb);
+      (void)nxsem_foreachholder(sem, nxsem_restoreholderprioB, stcb);
     }
 
   /* If there are no tasks waiting for available counts, then all holders
@@ -821,7 +822,7 @@ static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
 #ifdef CONFIG_DEBUG_ASSERTIONS
   else
     {
-      (void)sem_foreachholder(sem, sem_verifyholder, NULL);
+      (void)nxsem_foreachholder(sem, nxsem_verifyholder, NULL);
     }
 #endif
 
@@ -830,7 +831,7 @@ static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
    * counts, then we need to remove it from the list of holders.
    */
 
-  sem_findandfreeholder(sem, rtcb);
+  nxsem_findandfreeholder(sem, rtcb);
 }
 
 /****************************************************************************
@@ -838,10 +839,10 @@ static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_initholders
+ * Name: nxsem_initholders
  *
  * Description:
- *   Called from sem_initialize() to set up semaphore holder information.
+ *   Called from nxsem_initialize() to set up semaphore holder information.
  *
  * Parameters:
  *   None
@@ -853,7 +854,7 @@ static inline void sem_restorebaseprio_task(FAR struct tcb_s *stcb,
  *
  ****************************************************************************/
 
-void sem_initholders(void)
+void nxsem_initholders(void)
 {
 #if CONFIG_SEM_PREALLOCHOLDERS > 0
   int i;
@@ -871,11 +872,11 @@ void sem_initholders(void)
 }
 
 /****************************************************************************
- * Name: sem_destroyholder
+ * Name: nxsem_destroyholder
  *
  * Description:
- *   Called from sem_destroyholder() to handle any holders of a semaphore when
- *   it is destroyed.
+ *   Called from nxsem_destroyholder() to handle any holders of a semaphore
+ *   when it is destroyed.
  *
  * Parameters:
  *   sem - A reference to the semaphore being destroyed
@@ -887,7 +888,7 @@ void sem_initholders(void)
  *
  ****************************************************************************/
 
-void sem_destroyholder(FAR sem_t *sem)
+void nxsem_destroyholder(FAR sem_t *sem)
 {
   /* It is an error if a semaphore is destroyed while there are any holders
    * (except perhaps the thread release the semaphore itself).  Hmmm.. but
@@ -905,7 +906,7 @@ void sem_destroyholder(FAR sem_t *sem)
     {
       serr("ERROR: Semaphore destroyed with holders\n");
       DEBUGPANIC();
-      (void)sem_foreachholder(sem, sem_recoverholders, NULL);
+      (void)nxsem_foreachholder(sem, nxsem_recoverholders, NULL);
     }
 
 #else
@@ -921,7 +922,7 @@ void sem_destroyholder(FAR sem_t *sem)
 }
 
 /****************************************************************************
- * Name: sem_addholder_tcb
+ * Name: nxsem_addholder_tcb
  *
  * Description:
  *   Called from sem_wait() when the calling thread obtains the semaphore;
@@ -939,7 +940,7 @@ void sem_destroyholder(FAR sem_t *sem)
  *
  ****************************************************************************/
 
-void sem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem)
+void nxsem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem)
 {
   FAR struct semholder_s *pholder;
 
@@ -952,7 +953,7 @@ void sem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem)
     {
       /* Find or allocate a container for this new holder */
 
-      pholder = sem_findorallocateholder(sem, htcb);
+      pholder = nxsem_findorallocateholder(sem, htcb);
       if (pholder != NULL)
         {
           /* Then set the holder and increment the number of counts held by this
@@ -966,7 +967,7 @@ void sem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem)
 }
 
 /****************************************************************************
- * Name: sem_addholder
+ * Name: nxsem_addholder
  *
  * Description:
  *   Called from sem_wait() when the calling thread obtains the semaphore
@@ -982,13 +983,13 @@ void sem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem)
  *
  ****************************************************************************/
 
-void sem_addholder(FAR sem_t *sem)
+void nxsem_addholder(FAR sem_t *sem)
 {
-  sem_addholder_tcb(this_task(), sem);
+  nxsem_addholder_tcb(this_task(), sem);
 }
 
 /****************************************************************************
- * Name: void sem_boostpriority(sem_t *sem)
+ * Name: void nxsem_boostpriority(sem_t *sem)
  *
  * Description:
  *
@@ -1003,7 +1004,7 @@ void sem_addholder(FAR sem_t *sem)
  *
  ****************************************************************************/
 
-void sem_boostpriority(FAR sem_t *sem)
+void nxsem_boostpriority(FAR sem_t *sem)
 {
   FAR struct tcb_s *rtcb = this_task();
 
@@ -1012,11 +1013,11 @@ void sem_boostpriority(FAR sem_t *sem)
    * count.
    */
 
-  (void)sem_foreachholder(sem, sem_boostholderprio, rtcb);
+  (void)nxsem_foreachholder(sem, nxsem_boostholderprio, rtcb);
 }
 
 /****************************************************************************
- * Name: sem_releaseholder
+ * Name: nxsem_releaseholder
  *
  * Description:
  *   Called from sem_post() after a thread releases one count on the
@@ -1032,18 +1033,18 @@ void sem_boostpriority(FAR sem_t *sem)
  *
  ****************************************************************************/
 
-void sem_releaseholder(FAR sem_t *sem)
+void nxsem_releaseholder(FAR sem_t *sem)
 {
   FAR struct tcb_s *rtcb = this_task();
   FAR struct semholder_s *pholder;
 
   /* Find the container for this holder */
 
-  pholder = sem_findholder(sem, rtcb);
+  pholder = nxsem_findholder(sem, rtcb);
   if (pholder != NULL && pholder->counts > 0)
     {
       /* Decrement the counts on this holder -- the holder will be freed
-       * later in sem_restorebaseprio.
+       * later in nxsem_restorebaseprio.
        */
 
       pholder->counts--;
@@ -1051,7 +1052,7 @@ void sem_releaseholder(FAR sem_t *sem)
 }
 
 /****************************************************************************
- * Name: sem_restorebaseprio
+ * Name: nxsem_restorebaseprio
  *
  * Description:
  *   This function is called after the current running task releases a
@@ -1083,7 +1084,7 @@ void sem_releaseholder(FAR sem_t *sem)
  *
  ****************************************************************************/
 
-void sem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem)
+void nxsem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem)
 {
   /* Check our assumptions */
 
@@ -1100,19 +1101,19 @@ void sem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem)
 
   if (up_interrupt_context())
     {
-      sem_restorebaseprio_irq(stcb, sem);
+      nxsem_restorebaseprio_irq(stcb, sem);
     }
   else
     {
-      sem_restorebaseprio_task(stcb, sem);
+      nxsem_restorebaseprio_task(stcb, sem);
     }
 }
 
 /****************************************************************************
- * Name: sem_canceled
+ * Name: nxsem_canceled
  *
  * Description:
- *   Called from sem_waitirq() after a thread that was waiting for a semaphore
+ *   Called from nxsem_waitirq() after a thread that was waiting for a semaphore
  *   count was awakened because of a signal and the semaphore wait has been
  *   cancelled.  This function restores the correct thread priority of each
  *   holder of the semaphore.
@@ -1128,7 +1129,7 @@ void sem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem)
  ****************************************************************************/
 
 #ifndef CONFIG_DISABLE_SIGNALS
-void sem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem)
+void nxsem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem)
 {
   /* Check our assumptions */
 
@@ -1136,7 +1137,7 @@ void sem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem)
 
   /* Adjust the priority of every holder as necessary */
 
-  (void)sem_foreachholder(sem, sem_restoreholderprioall, stcb);
+  (void)nxsem_foreachholder(sem, nxsem_restoreholderprioall, stcb);
 }
 #endif
 
@@ -1160,13 +1161,13 @@ void sem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem)
 void sem_enumholders(FAR sem_t *sem)
 {
 #ifdef CONFIG_DEBUG_INFO
-  (void)sem_foreachholder(sem, sem_dumpholder, NULL);
+  (void)nxsem_foreachholder(sem, nxsem_dumpholder, NULL);
 #endif
 }
 #endif
 
 /****************************************************************************
- * Name: sem_nfreeholders
+ * Name: nxsem_nfreeholders
  *
  * Description:
  *   Return the number of available holder containers.  This is a good way
@@ -1183,7 +1184,7 @@ void sem_enumholders(FAR sem_t *sem)
  ****************************************************************************/
 
 #if defined(CONFIG_DEBUG_FEATURES) && defined(CONFIG_SEM_PHDEBUG)
-int sem_nfreeholders(void)
+int nxsem_nfreeholders(void)
 {
 #if CONFIG_SEM_PREALLOCHOLDERS > 0
   FAR struct semholder_s *pholder;
diff --git a/sched/semaphore/sem_initialize.c b/sched/semaphore/sem_initialize.c
index d91a8602fe..672ed86350 100644
--- a/sched/semaphore/sem_initialize.c
+++ b/sched/semaphore/sem_initialize.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * sched/semaphore/sem_initialize.c
+ * sched/semaphore/nxsem_initialize.c
  *
  *   Copyright (C) 2007, 2009, 2012, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -50,11 +50,11 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_initialize
+ * Name: nxsem_initialize
  *
  * Description:
  *   The control structures for all semaphores may be initialized by calling
- *   sem_initialize().  This should be done once at power-on.
+ *   nxsem_initialize().  This should be done once at power-on.
  *
  * Parameters:
  *   None
@@ -67,11 +67,11 @@
  *
  ****************************************************************************/
 
-void sem_initialize(void)
+void nxsem_initialize(void)
 {
   /* Initialize holder structures needed to support priority inheritance */
 
-  sem_initholders();
+  nxsem_initholders();
 }
 
 #endif /* CONFIG_PRIORITY_INHERITANCE */
diff --git a/sched/semaphore/sem_post.c b/sched/semaphore/sem_post.c
index 47487db42a..4309e482f3 100644
--- a/sched/semaphore/sem_post.c
+++ b/sched/semaphore/sem_post.c
@@ -103,7 +103,7 @@ int sem_post(FAR sem_t *sem)
        *
        * NOTE:  When semaphores are used for signaling purposes, the holder
        * of the semaphore may not be this thread!  In this case,
-       * sem_releaseholder() will do nothing.
+       * nxsem_releaseholder() will do nothing.
        *
        * In the case of a mutex this could be simply resolved since there is
        * only one holder but for the case of counting semaphores, there may
@@ -116,7 +116,7 @@ int sem_post(FAR sem_t *sem)
        */
 
       ASSERT(sem->semcount < SEM_VALUE_MAX);
-      sem_releaseholder(sem);
+      nxsem_releaseholder(sem);
       sem->semcount++;
 
 #ifdef CONFIG_PRIORITY_INHERITANCE
@@ -152,7 +152,7 @@ int sem_post(FAR sem_t *sem)
                * it is awakened.
                */
 
-              sem_addholder_tcb(stcb, sem);
+              nxsem_addholder_tcb(stcb, sem);
 
               /* It is, let the task take the semaphore */
 
@@ -170,7 +170,7 @@ int sem_post(FAR sem_t *sem)
        */
 
 #ifdef CONFIG_PRIORITY_INHERITANCE
-      sem_restorebaseprio(stcb, sem);
+      nxsem_restorebaseprio(stcb, sem);
       sched_unlock();
 #endif
       ret = OK;
diff --git a/sched/semaphore/sem_recover.c b/sched/semaphore/sem_recover.c
index 8b2d105b39..edeb30e037 100644
--- a/sched/semaphore/sem_recover.c
+++ b/sched/semaphore/sem_recover.c
@@ -50,7 +50,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_recover
+ * Name: nxsem_recover
  *
  * Description:
  *   This function is called from task_recover() when a task is deleted via
@@ -75,13 +75,13 @@
  *
  ****************************************************************************/
 
-void sem_recover(FAR struct tcb_s *tcb)
+void nxsem_recover(FAR struct tcb_s *tcb)
 {
   irqstate_t flags;
 
   /* The task is being deleted.  If it is waiting for a semphore, then
    * increment the count on the semaphores.  This logic is almost identical
-   * to what you see in sem_waitirq() except that no attempt is made to
+   * to what you see in nxsem_waitirq() except that no attempt is made to
    * restart the exiting task.
    *
    * NOTE:  In the case that the task is waiting we can assume: (1) That the
@@ -102,7 +102,7 @@ void sem_recover(FAR struct tcb_s *tcb)
        * to this semaphore.
        */
 
-      sem_canceled(tcb, sem);
+      nxsem_canceled(tcb, sem);
 
       /* And increment the count on the semaphore.  This releases the count
        * that was taken by sem_post().  This count decremented the semaphore
diff --git a/sched/semaphore/sem_reset.c b/sched/semaphore/sem_reset.c
index 4f98d4e8e3..7682671c2e 100644
--- a/sched/semaphore/sem_reset.c
+++ b/sched/semaphore/sem_reset.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * sched/semaphore/sem_reset.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,11 +52,11 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_reset
+ * Name: nxsem_reset
  *
  * Description:
  *   Reset a semaphore count to a specific value.  This is similar to part
- *   of the operation of sem_init().  But sem_reset() may need to wake up
+ *   of the operation of nxsem_init().  But nxsem_reset() may need to wake up
  *   tasks waiting on a count.  This kind of operation is sometimes required
  *   within the OS (only) for certain error handling conditions.
  *
@@ -65,11 +65,13 @@
  *   count - The requested semaphore count
  *
  * Return Value:
- *   0 (OK) or a negated errno value if unsuccessful
+ *   This is an internal OS interface, not available to applications, and
+ *   hence follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
  *
  ****************************************************************************/
 
-int sem_reset(FAR sem_t *sem, int16_t count)
+int nxsem_reset(FAR sem_t *sem, int16_t count)
 {
   irqstate_t flags;
 
diff --git a/sched/semaphore/sem_setprotocol.c b/sched/semaphore/sem_setprotocol.c
index 6f015bea4c..a991f70f0c 100644
--- a/sched/semaphore/sem_setprotocol.c
+++ b/sched/semaphore/sem_setprotocol.c
@@ -103,7 +103,7 @@ int sem_setprotocol(FAR sem_t *sem, int protocol)
 
         /* Remove any current holders */
 
-        sem_destroyholder(sem);
+        nxsem_destroyholder(sem);
         return OK;
 
       case SEM_PRIO_INHERIT:
diff --git a/sched/semaphore/sem_tickwait.c b/sched/semaphore/sem_tickwait.c
index a76308154a..8904ad92ce 100644
--- a/sched/semaphore/sem_tickwait.c
+++ b/sched/semaphore/sem_tickwait.c
@@ -1,7 +1,7 @@
 /****************************************************************************
- * sched/semaphore/sem_tickdwait.c
+ * sched/semaphore/sem_tickwait.c
  *
- *   Copyright (C) 2015-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -59,7 +59,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_tickwait
+ * Name: nxsem_tickwait
  *
  * Description:
  *   This function is a lighter weight version of sem_timedwait().  It is
@@ -76,12 +76,14 @@
  *             to sem_trywait().
  *
  * Return Value:
- *   Zero (OK) is returned on success.  A negated errno value is returned on
- *   failure.  -ETIMEDOUT is returned on the timeout condition.
+ *   This is an internal OS interface, not available to applications, and
+ *   hence follows the NuttX internal error return policy:  Zero (OK) is
+ *   returned on success.  A negated errno value is returned on failure.
+ *   -ETIMEDOUT is returned on the timeout condition.
  *
  ****************************************************************************/
 
-int sem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay)
+int nxsem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay)
 {
   FAR struct tcb_s *rtcb = this_task();
   irqstate_t flags;
@@ -147,7 +149,8 @@ int sem_tickwait(FAR sem_t *sem, systime_t start, uint32_t delay)
 
   /* Start the watchdog with interrupts still disabled */
 
-  (void)wd_start(rtcb->waitdog, delay, (wdentry_t)sem_timeout, 1, getpid());
+  (void)wd_start(rtcb->waitdog, delay, (wdentry_t)nxsem_timeout,
+                 1, getpid());
 
   /* Now perform the blocking wait */
 
diff --git a/sched/semaphore/sem_timedwait.c b/sched/semaphore/sem_timedwait.c
index 2ab32f6b86..f3348b5929 100644
--- a/sched/semaphore/sem_timedwait.c
+++ b/sched/semaphore/sem_timedwait.c
@@ -185,7 +185,8 @@ int sem_timedwait(FAR sem_t *sem, FAR const struct timespec *abstime)
 
   /* Start the watchdog */
 
-  (void)wd_start(rtcb->waitdog, ticks, (wdentry_t)sem_timeout, 1, getpid());
+  (void)wd_start(rtcb->waitdog, ticks, (wdentry_t)nxsem_timeout,
+                 1, getpid());
 
   /* Now perform the blocking wait */
 
diff --git a/sched/semaphore/sem_timeout.c b/sched/semaphore/sem_timeout.c
index 542724a94c..1d9c86d4f1 100644
--- a/sched/semaphore/sem_timeout.c
+++ b/sched/semaphore/sem_timeout.c
@@ -53,7 +53,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_timeout
+ * Name: nxsem_timeout
  *
  * Description:
  *   This function is called if the timeout elapses before before a
@@ -71,7 +71,7 @@
  *
  ****************************************************************************/
 
-void sem_timeout(int argc, wdparm_t pid)
+void nxsem_timeout(int argc, wdparm_t pid)
 {
   FAR struct tcb_s *wtcb;
   irqstate_t flags;
@@ -94,7 +94,7 @@ void sem_timeout(int argc, wdparm_t pid)
     {
       /* Cancel the semaphore wait */
 
-      sem_waitirq(wtcb, ETIMEDOUT);
+      nxsem_waitirq(wtcb, ETIMEDOUT);
     }
 
   /* Interrupts may now be enabled. */
diff --git a/sched/semaphore/sem_wait.c b/sched/semaphore/sem_wait.c
index c51cdcb1f0..2efd2719e7 100644
--- a/sched/semaphore/sem_wait.c
+++ b/sched/semaphore/sem_wait.c
@@ -121,7 +121,7 @@ int sem_wait(FAR sem_t *sem)
           /* It is, let the task take the semaphore. */
 
           sem->semcount--;
-          sem_addholder(sem);
+          nxsem_addholder(sem);
           rtcb->waitsem = NULL;
           ret = OK;
         }
@@ -161,7 +161,7 @@ int sem_wait(FAR sem_t *sem)
            * semaphore.
            */
 
-          sem_boostpriority(sem);
+          nxsem_boostpriority(sem);
 #endif
           /* Add the TCB to the prioritized semaphore wait queue */
 
@@ -177,7 +177,7 @@ int sem_wait(FAR sem_t *sem)
            * a timeout, certain semaphore clean-up operations have already been
            * performed (see sem_waitirq.c).  Specifically:
            *
-           * - sem_canceled() was called to restore the priority of all threads
+           * - nxsem_canceled() was called to restore the priority of all threads
            *   that hold a reference to the semaphore,
            * - The semaphore count was decremented, and
            * - tcb->waitsem was nullifed.
@@ -192,7 +192,7 @@ int sem_wait(FAR sem_t *sem)
             {
               /* Not awakened by a signal or a timeout...
                *
-               * NOTE that in this case sem_addholder() was called by logic
+               * NOTE that in this case nxsem_addholder() was called by logic
                * in sem_wait() fore this thread was restarted.
                */
 
diff --git a/sched/semaphore/sem_waitirq.c b/sched/semaphore/sem_waitirq.c
index 5ddafa62e0..ec74860c48 100644
--- a/sched/semaphore/sem_waitirq.c
+++ b/sched/semaphore/sem_waitirq.c
@@ -52,7 +52,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sem_waitirq
+ * Name: nxsem_waitirq
  *
  * Description:
  *   This function is called when either:
@@ -77,7 +77,7 @@
  *
  ****************************************************************************/
 
-void sem_waitirq(FAR struct tcb_s *wtcb, int errcode)
+void nxsem_waitirq(FAR struct tcb_s *wtcb, int errcode)
 {
   irqstate_t flags;
 
@@ -101,7 +101,7 @@ void sem_waitirq(FAR struct tcb_s *wtcb, int errcode)
        * to this semaphore.
        */
 
-      sem_canceled(wtcb, sem);
+      nxsem_canceled(wtcb, sem);
 
       /* And increment the count on the semaphore.  This releases the count
        * that was taken by sem_post().  This count decremented the semaphore
diff --git a/sched/semaphore/semaphore.h b/sched/semaphore/semaphore.h
index cc7a929816..f59345c9ce 100644
--- a/sched/semaphore/semaphore.h
+++ b/sched/semaphore/semaphore.h
@@ -64,49 +64,49 @@ extern "C"
 /* Common semaphore logic */
 
 #ifdef CONFIG_PRIORITY_INHERITANCE
-void sem_initialize(void);
+void nxsem_initialize(void);
 #else
-#  define sem_initialize()
+#  define nxsem_initialize()
 #endif
 
 /* Wake up a thread that is waiting on semaphore */
 
-void sem_waitirq(FAR struct tcb_s *wtcb, int errcode);
+void nxsem_waitirq(FAR struct tcb_s *wtcb, int errcode);
 
 /* Handle semaphore timer expiration */
 
-void sem_timeout(int argc, wdparm_t pid);
+void nxsem_timeout(int argc, wdparm_t pid);
 
 /* Recover semaphore resources with a task or thread is destroyed  */
 
-void sem_recover(FAR struct tcb_s *tcb);
+void nxsem_recover(FAR struct tcb_s *tcb);
 
 /* Special logic needed only by priority inheritance to manage collections of
  * holders of semaphores.
  */
 
 #ifdef CONFIG_PRIORITY_INHERITANCE
-void sem_initholders(void);
-void sem_destroyholder(FAR sem_t *sem);
-void sem_addholder(FAR sem_t *sem);
-void sem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem);
-void sem_boostpriority(FAR sem_t *sem);
-void sem_releaseholder(FAR sem_t *sem);
-void sem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem);
+void nxsem_initholders(void);
+void nxsem_destroyholder(FAR sem_t *sem);
+void nxsem_addholder(FAR sem_t *sem);
+void nxsem_addholder_tcb(FAR struct tcb_s *htcb, FAR sem_t *sem);
+void nxsem_boostpriority(FAR sem_t *sem);
+void nxsem_releaseholder(FAR sem_t *sem);
+void nxsem_restorebaseprio(FAR struct tcb_s *stcb, FAR sem_t *sem);
 #  ifndef CONFIG_DISABLE_SIGNALS
-void sem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem);
+void nxsem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem);
 #  else
-#    define sem_canceled(stcb, sem)
+#    define nxsem_canceled(stcb, sem)
 #  endif
 #else
-#  define sem_initholders()
-#  define sem_destroyholder(sem)
-#  define sem_addholder(sem)
-#  define sem_addholder_tcb(htcb,sem)
-#  define sem_boostpriority(sem)
-#  define sem_releaseholder(sem)
-#  define sem_restorebaseprio(stcb,sem)
-#  define sem_canceled(stcb,sem)
+#  define nxsem_initholders()
+#  define nxsem_destroyholder(sem)
+#  define nxsem_addholder(sem)
+#  define nxsem_addholder_tcb(htcb,sem)
+#  define nxsem_boostpriority(sem)
+#  define nxsem_releaseholder(sem)
+#  define nxsem_restorebaseprio(stcb,sem)
+#  define nxsem_canceled(stcb,sem)
 #endif
 
 #undef EXTERN
diff --git a/sched/signal/sig_dispatch.c b/sched/signal/sig_dispatch.c
index c69c6388f6..f3f01d8767 100644
--- a/sched/signal/sig_dispatch.c
+++ b/sched/signal/sig_dispatch.c
@@ -409,7 +409,7 @@ int sig_tcbdispatch(FAR struct tcb_s *stcb, siginfo_t *info)
 
       if (stcb->task_state == TSTATE_WAIT_SEM)
         {
-          sem_waitirq(stcb, EINTR);
+          nxsem_waitirq(stcb, EINTR);
         }
 
       /* If the task is blocked waiting on a message queue, then that task
diff --git a/sched/task/task_cancelpt.c b/sched/task/task_cancelpt.c
index 5aa6fa785f..ce194547d3 100644
--- a/sched/task/task_cancelpt.c
+++ b/sched/task/task_cancelpt.c
@@ -302,7 +302,7 @@ void notify_cancellation(FAR struct tcb_s *tcb)
 
       if (tcb->task_state == TSTATE_WAIT_SEM)
         {
-          sem_waitirq(tcb, ECANCELED);
+          nxsem_waitirq(tcb, ECANCELED);
         }
 
       /* If the thread is blocked waiting on a message queue, then the
diff --git a/sched/task/task_recover.c b/sched/task/task_recover.c
index b474eba995..8f563cf122 100644
--- a/sched/task/task_recover.c
+++ b/sched/task/task_recover.c
@@ -84,7 +84,7 @@ void task_recover(FAR struct tcb_s *tcb)
    * then release the counts.
    */
 
-  sem_recover(tcb);
+  nxsem_recover(tcb);
 
 #ifndef CONFIG_DISABLE_MQUEUE
   /* Handle cases where the thread was waiting for a message queue event */
diff --git a/wireless/ieee802154/mac802154.c b/wireless/ieee802154/mac802154.c
index fc16cba0ec..58937a3f20 100644
--- a/wireless/ieee802154/mac802154.c
+++ b/wireless/ieee802154/mac802154.c
@@ -130,7 +130,7 @@ static void mac802154_resetqueues(FAR struct ieee802154_privmac_s *priv)
       sq_addlast((FAR sq_entry_t *)&priv->txdesc_pool[i], &priv->txdesc_queue);
     }
 
-  sem_init(&priv->txdesc_sem, 0, CONFIG_MAC802154_NTXDESC);
+  nxsem_init(&priv->txdesc_sem, 0, CONFIG_MAC802154_NTXDESC);
 
   /* Initialize the notifcation allocation pool */
 
@@ -1963,11 +1963,11 @@ MACHANDLE mac802154_create(FAR struct ieee802154_radio_s *radiodev)
 
   /* Allow exclusive access to the privmac struct */
 
-  sem_init(&mac->exclsem, 0, 1);
+  nxsem_init(&mac->exclsem, 0, 1);
 
   /* Allow exclusive access to the dedicated command transaction */
 
-  sem_init(&mac->opsem, 0, 1);
+  nxsem_init(&mac->opsem, 0, 1);
 
   /* Initialize fields */
 
diff --git a/wireless/ieee802154/mac802154_device.c b/wireless/ieee802154/mac802154_device.c
index d3c689d933..99ea797e8b 100644
--- a/wireless/ieee802154/mac802154_device.c
+++ b/wireless/ieee802154/mac802154_device.c
@@ -898,17 +898,17 @@ int mac802154dev_register(MACHANDLE mac, int minor)
   /* Initialize the new mac driver instance */
 
   dev->md_mac = mac;
-  sem_init(&dev->md_exclsem, 0, 1); /* Allow the device to be opened once
-                                     * before blocking */
+  nxsem_init(&dev->md_exclsem, 0, 1); /* Allow the device to be opened once
+                                       * before blocking */
 
-  sem_init(&dev->readsem, 0, 0);
+  nxsem_init(&dev->readsem, 0, 0);
   sem_setprotocol(&dev->readsem, SEM_PRIO_NONE);
   dev->readpending = false;
 
   sq_init(&dev->dataind_queue);
 
   dev->geteventpending = false;
-  sem_init(&dev->geteventsem, 0, 0);
+  nxsem_init(&dev->geteventsem, 0, 0);
   sem_setprotocol(&dev->geteventsem, SEM_PRIO_NONE);
 
   dev->event_head = NULL;
diff --git a/wireless/ieee802154/mac802154_netdev.c b/wireless/ieee802154/mac802154_netdev.c
index 54f4d8f942..f65e298b87 100644
--- a/wireless/ieee802154/mac802154_netdev.c
+++ b/wireless/ieee802154/mac802154_netdev.c
@@ -1460,7 +1460,7 @@ int mac802154netdev_register(MACHANDLE mac)
 
   /* Setup a locking semaphore for exclusive device driver access */
 
-  sem_init(&priv->md_exclsem, 0, 1);
+  nxsem_init(&priv->md_exclsem, 0, 1);
 
   DEBUGASSERT(priv->md_txpoll != NULL);
 
@@ -1477,7 +1477,7 @@ int mac802154netdev_register(MACHANDLE mac)
   /* Initialize fields related to MAC event handling */
 
   priv->md_eventpending = false;
-  sem_init(&priv->md_eventsem, 0, 0);
+  nxsem_init(&priv->md_eventsem, 0, 0);
   sem_setprotocol(&priv->md_eventsem, SEM_PRIO_NONE);
 
   priv->md_eventhead = NULL;
diff --git a/wireless/ieee802154/mac802154_notif.c b/wireless/ieee802154/mac802154_notif.c
index 0d2727c0e1..ebad344f38 100644
--- a/wireless/ieee802154/mac802154_notif.c
+++ b/wireless/ieee802154/mac802154_notif.c
@@ -124,7 +124,7 @@ void mac802154_notifpool_init(FAR struct ieee802154_privmac_s *priv)
       remaining--;
     }
 
-  sem_init(&priv->notif_sem, 0, CONFIG_MAC802154_NNOTIF);
+  nxsem_init(&priv->notif_sem, 0, CONFIG_MAC802154_NNOTIF);
 }
 
 /****************************************************************************
diff --git a/wireless/pktradio/pktradio_metadata.c b/wireless/pktradio/pktradio_metadata.c
index be819d19aa..1f9d198639 100644
--- a/wireless/pktradio/pktradio_metadata.c
+++ b/wireless/pktradio/pktradio_metadata.c
@@ -120,7 +120,7 @@ void pktradio_metadata_initialize(void)
 
       /* Initialize the mutual exclusion semaphore */
 
-      sem_init(&g_metadata_sem, 0, 1);
+      nxsem_init(&g_metadata_sem, 0, 1);
       g_metadata_initialized = true;
     }
 }