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sem_close(2) [osx man page]

SEM_CLOSE(2)						      BSD System Calls Manual						      SEM_CLOSE(2)

sem_close -- close a named semaphore SYNOPSIS
#include <semaphore.h> int sem_close(sem_t *sem); DESCRIPTION
The system resources associated with the named semaphore referenced by sem are deallocated and the descriptor is invalidated. If successful, sem_close() will return 0. Otherwise, -1 is returned and errno is set. ERRORS
sem_close() succeeds unless: [EINVAL] sem is not a valid semaphore descriptor. SEE ALSO
sem_init(2), sem_open(2), sem_unlink(2), semctl(2), semget(2), semop(2) HISTORY
sem_close() is specified in the POSIX Realtime Extension (1003.1b-1993/1003.1i-1995). Darwin June 8, 2000 Darwin

Check Out this Related Man Page

sem_close(3)						     Library Functions Manual						      sem_close(3)

sem_close - Deallocates the specified named semaphore (P1003.1b) LIBRARY
Realtime Library (, 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)
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