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sem_init(3)

sem_open(3)

sem_destroy(3)  —  Subroutines

NAME

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

SYNOPSIS

#include <semaphore.h>
 
int sem_destroy (
sem_t ∗sem);

LIBRARY

Realtime Library (librt.so, librt.a)

PARAMETERS

semReferences the unnamed semaphore to be destroyed. Use the sem argument that was supplied to, and filled in by, the previous call to sem_init. 

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 that has not yet opened the semaphore. 

RETURN VALUES

On successful completion, the function returns the value 0 (zero); 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. 

SEE ALSO

Functions: sem_init(3), sem_open(3)

Guide to Realtime Programming

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