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MQ_UNLINK(2) FreeBSD System Calls Manual MQ_UNLINK(2)
NAME
mq_unlink - 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 string
name. 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. However, the
mq_unlink() call need not block until all references have been closed; it
may return immediately.
After a successful call to mq_unlink(), reuse of the name will
subsequently cause mq_open(2) to behave as if no message queue of this
name exists.
RETURN VALUES
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
The mq_unlink() system call will fail if:
[EACCESS] Permission is denied to unlink the message queue
represented by name.
[EINVAL] name is invalid.
[ENAMETOOLONG] The length of the name argument exceeds {PATH_MAX} or
a pathname component is longer than {NAME_MAX}.
[ENOENT] The message queue does not exist.
[ENOSYS] mqueuefs(5) module is neither loaded nor included in
the kernel.
SEE ALSO
mq_open(2)
STANDARDS
The mq_unlink() system call conforms to IEEE Std 1003.1-2004 ("POSIX.1").
The [EACCESS] error code is an extension to the standard.
HISTORY
Support for POSIX message queues first appeared in FreeBSD 7.0.
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
http://www.opengroup.org/unix/online.html.
FreeBSD 14.2-RELEASE February 15, 2021 FreeBSD 14.2-RELEASE