sem_destroy(3) [freebsd man page]

SEM_DESTROY(3)						   BSD Library Functions Manual 					    SEM_DESTROY(3)

NAME

     sem_destroy -- destroy an unnamed semaphore

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <semaphore.h>

     int
     sem_destroy(sem_t *sem);

DESCRIPTION

     The sem_destroy() function destroys the unnamed semaphore pointed to by sem.  After a successful call to sem_destroy(), sem is unusable until
     re-initialized by another call to sem_init(3).

RETURN VALUES

     The sem_destroy() 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

     The sem_destroy() function will fail if:

     [EINVAL]		The sem argument points to an invalid semaphore.

     [EBUSY]		There are currently threads blocked on the semaphore that sem points to.

SEE ALSO

     sem_init(3)

STANDARDS

     The sem_destroy() function conforms to ISO/IEC 9945-1:1996 (``POSIX.1'').

     POSIX does not define the behavior of sem_destroy() if called while there are threads blocked on sem, but this implementation is guaranteed
     to return -1 and set errno to EBUSY if there are threads blocked on sem.

BSD
								 February 15, 2000							       BSD

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.

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 implementations.

SEE ALSO

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

COLOPHON

       This page is part of release 3.53 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

Linux								    2012-05-13							    SEM_DESTROY(3)