MQ_UNLINK(3) Library Functions Manual MQ_UNLINK(3)

mq_unlink — remove a message queue (REALTIME)


#include <mqueue.h>

int mq_unlink(const char *name);

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(3) with name shall fail if the flag O_CREAT is not set in . 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(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.

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 to indicate the error.

The mq_unlink () function shall fail if:

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

None.

None.

None.

None.

mq_close(3), mq_open(3), msgctl(3), msgget(3), msgrcv(3), msgsnd(3), the Base Definitions volume of IEEE Std 1003.1-2001 (“POSIX.1”), <mqueue.h>

First released in Issue 5. Included for alignment with the POSIX Realtime Extension.

The mq_unlink () function is marked as part of the Message Passing option.

The Open Group Corrigendum U021/5 is applied, clarifying that upon unsuccessful completion, the named message queue is unchanged by this function.

The [ENOSYS] error condition has been removed as stubs need not be provided if an implementation does not support the Message Passing option.

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January 1, 2004 posix.fail