diff --git a/include/stdlib.h b/include/stdlib.h
index f186dc5245..b29e59a5bd 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -132,6 +132,7 @@ extern "C"
 
 void      srand(unsigned int seed);
 int       rand(void);
+int       rand_r(FAR unsigned int *seedp);
 void      lcong48(FAR unsigned short int param[7]);
 FAR unsigned short int *seed48(FAR unsigned short int seed16v[3]);
 void      srand48(long int seedval);
diff --git a/libs/libc/stdlib/lib_srand.c b/libs/libc/stdlib/lib_srand.c
index 80df76fe5e..4e0d157d8b 100644
--- a/libs/libc/stdlib/lib_srand.c
+++ b/libs/libc/stdlib/lib_srand.c
@@ -67,9 +67,9 @@ typedef double       float_t;
 
 /* First order congruential generators */
 
-static inline unsigned long fgenerate1(void);
+static inline unsigned long fgenerate1(FAR unsigned long *seed);
 #if (CONFIG_LIBC_RAND_ORDER == 1)
-static float_t frand1(void);
+static float_t frand1(FAR unsigned long *seed);
 #endif
 
 /* Second order congruential generators */
@@ -106,7 +106,7 @@ static unsigned long g_randint3;
 
 /* First order congruential generators */
 
-static inline unsigned long fgenerate1(void)
+static inline unsigned long fgenerate1(FAR unsigned long *seed)
 {
   unsigned long randint;
 
@@ -115,17 +115,17 @@ static inline unsigned long fgenerate1(void)
    * the first order random number generator.
    */
 
-  randint    = (RND1_CONSTK * g_randint1) % RND1_CONSTP;
-  g_randint1 = (randint == 0 ? 1 : randint);
+  randint = (RND1_CONSTK * (*seed)) % RND1_CONSTP;
+  *seed   = (randint == 0 ? 1 : randint);
   return randint;
 }
 
 #if (CONFIG_LIBC_RAND_ORDER == 1)
-static float_t frand1(void)
+static float_t frand1(FAR unsigned long *seed)
 {
   /* First order congruential generator. */
 
-  unsigned long randint = fgenerate1();
+  unsigned long randint = fgenerate1(seed);
 
   /* Construct an floating point value in the range from 0.0 up to 1.0 */
 
@@ -215,40 +215,8 @@ static float_t frand3(void)
 #endif
 #endif
 
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: srand
- *
- * Description:
- *   Seed the congruential random number generator.
- *
- ****************************************************************************/
-
-void srand(unsigned int seed)
-{
-  g_randint1 = seed;
-#if (CONFIG_LIBC_RAND_ORDER > 1)
-  g_randint2 = seed;
-  fgenerate1();
-#if (CONFIG_LIBC_RAND_ORDER > 2)
-  g_randint3 = seed;
-  fgenerate2();
-#endif
-#endif
-}
-
-/****************************************************************************
- * Name: nrand
- *
- * Description:
- *   Return a random, unsigned long value in the range of 0 to (limit - 1)
- *
- ****************************************************************************/
-
-unsigned long nrand(unsigned long limit)
+static unsigned long nrand_r(unsigned long limit,
+                             FAR unsigned long *seed)
 {
   unsigned long result;
   float_t ratio;
@@ -260,7 +228,7 @@ unsigned long nrand(unsigned long limit)
       /* Get a random integer in the range 0.0 - 1.0 */
 
 #if (CONFIG_LIBC_RAND_ORDER == 1)
-      ratio = frand1();
+      ratio = frand1(seed);
 #elif (CONFIG_LIBC_RAND_ORDER == 2)
       ratio = frand2();
 #else /* if (CONFIG_LIBC_RAND_ORDER > 2) */
@@ -279,3 +247,65 @@ unsigned long nrand(unsigned long limit)
 
   return result;
 }
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: srand
+ *
+ * Description:
+ *   Seed the congruential random number generator.
+ *
+ ****************************************************************************/
+
+void srand(unsigned int seed)
+{
+  g_randint1 = seed;
+#if (CONFIG_LIBC_RAND_ORDER > 1)
+  g_randint2 = seed;
+  fgenerate1(&g_randint1);
+#if (CONFIG_LIBC_RAND_ORDER > 2)
+  g_randint3 = seed;
+  fgenerate2();
+#endif
+#endif
+}
+
+/****************************************************************************
+ * Name: nrand
+ *
+ * Description:
+ *   Return a random, unsigned long value in the range of 0 to (limit - 1)
+ *
+ ****************************************************************************/
+
+unsigned long nrand(unsigned long limit)
+{
+  return nrand_r(limit, &g_randint1);
+}
+
+/****************************************************************************
+ * Name: rand_r
+ *
+ * Description:
+ *   The function rand() is not reentrant, since it uses hidden state that
+ *   is modified on each call. This might just be the seed value to be used
+ *   by the next call, or it might be something more elaborate. In order to
+ *   get reproducible behavior in a threaded application, this state must be
+ *   made explicit; this can be done using the reentrant function rand_r().
+ *
+ *   Return a random, int value in the range of 0 to INT_MAX.
+ *
+ ****************************************************************************/
+
+int rand_r(FAR unsigned int *seedp)
+{
+  unsigned long seed = *seedp;
+  unsigned long rand;
+
+  rand = nrand_r(INT_MAX, &seed);
+  *seedp = (unsigned int)seed;
+  return (int)rand;
+}