SEM_DESTROY(3)                      Linux Programmer's Manual                      SEM_DESTROY(3)



NAME
       sem_destroy - destroy an unnamed semaphore

SYNOPSIS
       #include <semaphore.h>

       int sem_destroy(sem_t *sem);

       Link with -pthread.

DESCRIPTION
       sem_destroy() destroys the unnamed semaphore at the address pointed to by sem.

       Only  a  semaphore  that  has  been  initialized  by sem_init(3) should be destroyed using
       sem_destroy().

       Destroying a semaphore that other processes  or  threads  are  currently  blocked  on  (in
       sem_wait(3)) produces undefined behavior.

       Using  a semaphore that has been destroyed produces undefined results, until the semaphore
       has been reinitialized using sem_init(3).

RETURN VALUE
       sem_destroy() returns 0 on success; on error, -1 is returned, and errno is set to indicate
       the error.

ERRORS
       EINVAL sem is not a valid semaphore.

ATTRIBUTES
   Multithreading (see pthreads(7))
       The sem_destroy() function is thread-safe.

CONFORMING TO
       POSIX.1-2001.

NOTES
       An  unnamed semaphore should be destroyed with sem_destroy() before the memory in which it
       is located is deallocated.  Failure to do this can result in resource leaks on some imple‐
       mentations.

SEE ALSO
       sem_init(3), sem_post(3), sem_wait(3), sem_overview(7)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



Linux                                       2014-03-03                             SEM_DESTROY(3)