The mq_unlink() function shall remove the message queue named by the
pathname name. After a successful call to mq_unlink() with
name, a call to mq_open() with name shall fail 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 shall be postponed until all references to the message queue
have been closed.
Calls to mq_open() 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.
Upon successful completion, the function shall return a value of zero.
Otherwise, the named message queue shall be unchanged by this function call,
and the function shall return a value of -1 and set errno to indicate
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