sem_destroy(PTHREAD)

sem_destroy -- destroy an unnamed semaphore

Synopsis

   cc [options] -Kthread file
   
   #include <semaphore.h>
   

   int sem_destroy(sem_t *sem);

Description

sem_destroy destroys the semaphore pointed to by sem. This includes invalidating sem and freeing any associated dynamically allocated resources.

Only a semaphore that was previously initialized by sem_init may be destroyed using sem_destroy;

It is safe to destroy an initialized semaphore upon which no threads are currently blocked. The effect of destroying a semaphore upon which other threads are currently blocked is undefined.

Return values

sem_destroy returns zero on success. Otherwise, a value of -1 is returned and errno is set to indicate the error.

Errors

sem_destroy returns the following value if the corresponding condition is detected:

EINVAL: The sem argument is not a valid semaphore.
EBUSY: There are currently threads blocked on the semaphore.

Standards compliance

The Single UNIX Specification, Version 2; The Open Group.

References

Intro(PTHREAD), sem_init(PTHREAD), sem_open(PTHREAD), sem_post(PTHREAD), sem_trywait(PTHREAD), sem_wait(PTHREAD), semaphore(F)