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sem_close(3) Library Functions Manual sem_close(3) NAME
sem_close - Deallocates the specified named semaphore (P1003.1b) LIBRARY
Realtime Library (librt.so, librt.a) SYNOPSIS
#include <semaphore.h> int sem_close ( sem_t *sem) ; PARAMETERS
sem References the semaphore to be closed. Use the sem argument returned by the previous call to sem_open. DESCRIPTION
The sem_close function makes a semaphore available for reuse by deallocating any system resources allocated for use by the current process for the named semaphore indicated by sem. If the semaphore has not been removed with a call to sem_unlink, sem_close does not change the current state of the semaphore. If the semaphore has been removed with a call to sem_unlink after the most recent call to sem_open with O_CREAT, the semaphore is no longer available after all processes that opened the semaphore close it. RETURN VALUES
On a successful call, a value of 0 (zero) is returned. Otherwise, a value of -1 is returned and errno is set to indicate that an error occurred. ERRORS
The sem_close function fails under the following condition: [EINVAL] The sem argument is not a valid semaphore descriptor. RELATED INFORMATION
Functions: sem_init(3), sem_open(3), sem_unlink(3) Guide to Realtime Programming delim off sem_close(3)
