NAME

sem_destroy − Destroy an unnamed semaphore (P1003.1b)

SYNOPSIS

#include <semaphore.h>

int sem_destroy (
sem_t ∗sem);

PARAMETERS

sem References the unnamed semaphore to be destroyed.  Use the sem argument originally supplied with the appropriate sem_init function. 

DESCRIPTION

The sem_destroy function destroys an unnamed semaphore indicated by sem.  Only a semaphore created using sem_init may be destroyed using sem_destroy. 

The potential for deadlock exists if a process calls sem_destroy for a semaphore while there is a pending sem_wait, because a process may be waiting for a poster which has not yet opened the semaphore. 

RETURN VALUES

On successful completion, the function returns the value 0; otherwise, the function returns the value −1 and sets errno to indicate the error, without destroying the semaphore indicated by the sem argument. 

ERRORS

The sem_destroy function fails under the following condition:

[EINVAL] The sem argument is not a valid semaphore. 

RELATED INFORMATION

Functions: sem_init(3), sem_open(3)