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On Fri, 26 Mar 1999, Michael Ambrus wrote: > Where can I find a lib implementing POSIX 1003.1b . > Hi, Courtesy of John Bossom, Pthreads-win32 has an implementation of semaphores, but those functions aren't exported, just used internally. This is because they aren't 100% according to the standard, as the following comments from John's code explains. * Module: semaphore.c * * Purpose: * Semaphores aren't actually part of the PThreads standard. * They are defined by the POSIX Standard: * * POSIX 1003.1b-1993 (POSIX.1b) * * They are supposed to follow the older UNIX convention for * reporting errors. That is, on failure they are supposed * to return a value of -1 and store the appropriate error * number into 'errno'. * HOWEVER,errno cannot be modified in a multithreaded * program on WIN32; therefore, the value is returned as * the function value. * It is recommended that you compare for zero (0) for success * instead of -1 for failure when checking the status of * these functions. * * Contents: * Public Methods Author * -------------- ------ * sem_init John E. Bossom Mar 1998 * sem_destroy John E. Bossom Mar 1998 * sem_trywait John E. Bossom Mar 1998 * sem_wait John E. Bossom Mar 1998 * sem_post John E. Bossom Mar 1998 You are, of course, free to take this code and build your own POSIX.1b library. What is really needed is a thread-safe errno variable, which can be implemented but it needs to be done in a way that is compatible across the whole POSIX implementation. I decided to leave that to others such as the Cygwin project. Ross +----------------------+---+ | Ross Johnson | | E-Mail: rpj@ise.canberra.edu.au | Info Sciences and Eng|___| | University of Canberra | FAX: +61 6 2015227 | PO Box 1 | | Belconnen ACT 2616 | WWW: http://willow.canberra.edu.au/~rpj/ | AUSTRALIA | +--------------------------+