Name
sem_destroy - destroy an unnamed semaphoreLibrary
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 bysem. 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).| Interface | Attribute | Value |
| T} | Thread safety | MT-Safe |
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)