sem_unlink()

Destroy a named semaphore

Synopsis:

#include <semaphore.h>

int sem_unlink( const char * sem_name );

Library:

libc

Description:

The sem_unlink() function destroys the named semaphore, sem_name. Open semaphores are removed the same way unlink() removes open files; the processes that have the semaphore open can still use it, but the semaphore will disappear as soon as the last process uses sem_close() to close it. Any attempt to sem_open() an unlinked semaphore will refer to a new semaphore.

Semaphores are persistent as long as the system remains up.

Returns:

0

Success.

-1

An error occurred (errno is set).

Errors:

EACCESS

You don't have permission to unlink the semaphore.

ELOOP

Too many levels of symbolic links or prefixes.

ENOENT

The semaphore sem_name doesn't exist.

ENAMETOOLONG

The sem_name argument is longer than (NAME_MAX - 8).

ENOSYS

The sem_unlink() function isn't implemented for the filesystem specified in path.

Classification:

POSIX 1003.1

Caveats:

The mqueue manager must be running for applications to use named semaphores.

See also:

sem_open(), sem_close(), sem_wait(), sem_trywait(), sem_post()