xref: /titanic_51/usr/src/man/man3c/sem_unlink.3c (revision ce0d9371c4da921f289a8bc7fd846d3bf1b8cca7)
te
Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved.
Copyright 1989 AT&T
Portions Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
SEM_UNLINK 3C "Feb 5, 2008"
NAME
sem_unlink - remove a named semaphore
SYNOPSIS

#include <semaphore.h>

int sem_unlink(const char *name);
DESCRIPTION

The sem_unlink() function removes the semaphore named by the string name. If the semaphore named by name is currently referenced by other processes, then sem_unlink() has no effect on the state of the semaphore. If one or more processes have the semaphore open when sem_unlink() is called, destruction of the semaphore is postponed until all references to the semaphore have been destroyed by calls to sem_close(3C), _Exit(2), or one of the exec functions (see exec(2)) . Calls to sem_open(3C) to re-create or re-connect to the semaphore refer to a new semaphore after sem_unlink() is called. The sem_unlink() call does not block until all references have been destroyed; it returns immediately.

RETURN VALUES

Upon successful completion, sem_unlink() returns 0. Otherwise, the semaphore is not changed and the function returns a value of -1 and sets errno to indicate the error.

ERRORS

The sem_unlink() function will fail if: EACCES

Permission is denied to unlink the named semaphore.

ENAMETOOLONG

The length of name string exceeds PATH_MAX, or a pathname component is longer than NAME_MAX while _POSIX_NO_TRUNC is in effect.

ENOENT

The named semaphore does not exist.

ENOSYS

The sem_unlink() function is not supported by the system.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Committed
MT-Level MT-Safe
Standard See standards(5).
SEE ALSO

exec(2), exit(2), sem_close(3C), sem_open(3C), attributes(5), standards(5)

NOTES

Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned -1 and set errno to ENOSYS.