sem_destroy - Man Page

destroy an unnamed semaphore


#include <semaphore.h>

int sem_destroy(sem_t *sem);

Link with -pthread.


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.



sem is not a valid semaphore.


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

sem_destroy()Thread safetyMT-Safe

Conforming to

POSIX.1-2001, POSIX.1-2008.


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)


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Referenced By

sem_init(3), sem_overview(7).

2021-03-22 Linux Programmer's Manual