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MQ_UNLINK(2)             DragonFly System Calls Manual            MQ_UNLINK(2)


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(2) 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 ref-
     erences to the message queue have been closed.

     Calls to mq_open(2) to recreate the message queue may fail until the mes-
     sage 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.  Other-
     wise, 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_close(2), mq_getattr(2), mq_notify(2), mq_open(2), mq_receive(2),
     mq_send(2), mq_setattr(2)


STANDARDS

     This function conforms to the IEEE Std 1003.1-2001 (``POSIX.1'') stan-
     dard.


HISTORY

     The mq_unlink() function first appeared in DragonFly 2.5.


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 Spec-
     ifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electri-
     cal 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 ref-
     eree document.  The original Standard can be obtained online at
     http://www.opengroup.org/unix/online.html .

DragonFly 3.5                   August 19, 2009                  DragonFly 3.5

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