NAME¶

sem_destroy - destroy an unnamed semaphore

LIBRARY¶

POSIX threads library (libpthread, -lpthread)

SYNOPSIS¶

#include <semaphore.h>

int sem_destroy(sem_t *sem);

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¶

For an explanation of the terms used in this section, see attributes(7).

STANDARDS¶

POSIX.1-2008.

HISTORY¶

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)