MQ_UNLINK(3)

MQ_UNLINK(3) | Library Functions Manual | MQ_UNLINK(3)

# NAME

mq_unlink — remove a message queue (REALTIME)

# LIBRARY

POSIX Real-time Library (librt, -lrt)

# SYNOPSIS

#include <mqueue.h>
int
mq_unlink(const char *name);

# DESCRIPTION

The mq_unlink() function removes the message queue named by the pathname name. After a successful call to mq_unlink() with name, a call to mq_open(3) with name fails if the flag `O_CREAT` is not set in flags. If one or more processes have the message queue open when mq_unlink() is called, destruction of the message queue will be postponed until all references to the message queue have been closed.
Calls to mq_open(3) to recreate the message queue may fail until the message queue is actually removed. However, the mq_unlink() call need not block until all references have been closed; it may return immediately.

# RETURN VALUES

Upon successful completion, the function returns a value of zero. Otherwise, the named message queue will be unchanged by this function call, and the function returns a value of -1 and sets the global variable errno to indicate the error.

# ERRORS

The mq_unlink() function fails if:

[`EACCES`]
  Permission is denied to unlink the named message queue.
[`ENAMETOOLONG`]
  The length of the name argument exceeds {`PATH_MAX`} or a pathname component is longer than {`NAME_MAX`}.
[`ENOENT`]
  The named message queue does not exist.

# SEE ALSO

mq(3), mq_open(3)

# STANDARDS

This function conforms to the IEEE Std 1003.1-2001 (“POSIX.1”) standard.

# HISTORY

The mq_unlink() function first appeared in NetBSD 5.0.

# COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version 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.

June 7, 2009 | NetBSD 8.3