I would appreciate any donations. Wishlist or send e-mail type donations to maekawa AT daemon-systems.org.
SEM_POST(3) Library Functions Manual SEM_POST(3) NAME sem_post -- increment (unlock) a semaphore LIBRARY POSIX Real-time Library (librt, -lrt) SYNOPSIS #include <semaphore.h> int sem_post(sem_t *sem); DESCRIPTION The sem_post() function increments (unlocks) the semaphore pointed to by sem. If there are threads blocked on the semaphore when sem_post() is called, then the highest priority thread that has been blocked the longest on the semaphore will be allowed to return from sem_wait() or sem_timedwait(). sem_post() is signal-reentrant and may be called within signal handlers. RETURN VALUES The sem_post() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error. ERRORS sem_post() will fail if: [EINVAL] sem points to an invalid semaphore. SEE ALSO sem_timedwait(3), sem_trywait(3), sem_wait(3) STANDARDS sem_post() conforms to ISO/IEC 9945-1:1996 (``POSIX.1''). NetBSD 7.1.2 February 29, 2012 NetBSD 7.1.2