/**************************************************************************** * libs/libc/misc/lib_mkfifo.c * * Copyright (C) 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #if defined(CONFIG_PIPES) && CONFIG_DEV_FIFO_SIZE > 0 /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: mkfifo * * Description: * mkfifo() makes a FIFO device driver file with name 'pathname.' Unlike * Linux, a NuttX FIFO is not a special file type but simply a device * driver instance. 'mode' specifies the FIFO's permissions. * * Once the FIFO has been created by mkfifo(), any thread can open it for * reading or writing, in the same way as an ordinary file. However, it * must have been opened from both reading and writing before input or * output can be performed. This FIFO implementation will block all * attempts to open a FIFO read-only until at least one thread has opened * the FIFO for writing. * * If all threads that write to the FIFO have closed, subsequent calls to * read() on the FIFO will return 0 (end-of-file). * * Input Parameters: * pathname - The full path to the FIFO instance to attach to or to create * (if not already created). * mode - Ignored for now * * Returned Value: * 0 is returned on success; otherwise, -1 is returned with errno set * appropriately. * ****************************************************************************/ int mkfifo(FAR const char *pathname, mode_t mode) { int ret; ret = nx_mkfifo(pathname, mode, CONFIG_DEV_FIFO_SIZE); if (ret < 0) { set_errno(-ret); ret = ERROR; } return ret; } #endif /* CONFIG_PIPES && CONFIG_DEV_FIFO_SIZE > 0 */