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

sem_destroy - 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).

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).
Interface Attribute Value
sem_destroy () Thread safety MT-Safe

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.

sem_init(3), sem_post(3), sem_wait(3), sem_overview(7)
2017-09-15 Linux