Content-type: text/html Man page of sem_close

sem_close

Section: C Library Functions (3)
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NAME

sem_close - Deallocate the specified named semaphore (P1003.1b)  

SYNOPSIS

#include <semaphore.h>

int sem_close (
sem_t *sem) ;  

PARAMETERS

sem
Pointer to the semaphore descriptor. 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 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) delim off


 

Index

NAME
SYNOPSIS
PARAMETERS
DESCRIPTION
RETURN VALUES
ERRORS
RELATED INFORMATION

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Time: 02:40:46 GMT, October 02, 2010