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Top Forums Programming POSIX message queue mq_open directory Post 302653877 by Corona688 on Monday 11th of June 2012 12:49:19 AM
Old 06-11-2012
They're still not 'real' files. Like /proc/, it's a special filesystem that exists only in the kernel's imagination.
 

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MQ_UNLINK(3P)						     POSIX Programmer's Manual						     MQ_UNLINK(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond- ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME
mq_unlink - remove a message queue (REALTIME) SYNOPSIS
#include <mqueue.h> int mq_unlink(const char *name); DESCRIPTION
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. RETURN VALUE
Upon successful completion, the function shall return a value of zero. Otherwise, the named message queue shall be unchanged by this func- tion call, and the function shall return a value of -1 and set errno to indicate the error. ERRORS
The mq_unlink() function shall fail 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. The following sections are informative. EXAMPLES
None. APPLICATION USAGE
None. RATIONALE
None. FUTURE DIRECTIONS
None. SEE ALSO
mq_close(), mq_open(), msgctl(), msgget(), msgrcv(), msgsnd(), the Base Definitions volume of IEEE Std 1003.1-2001, <mqueue.h> COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol- ogy -- 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 . IEEE
/The Open Group 2003 MQ_UNLINK(3P)
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