NAME
mq_close() — close a message queue descriptor
SYNOPSIS
#include <sys/mqueue.h>
int mq_close(mqd_t mqdes);
DESCRIPTION
The
mq_close()
system call removes the association between the message queue descriptor,
mqdes,
and a message queue. Use of this message queue descriptor by the process,
after a successful return from this
mq_close(),
and until this descriptor is returned by a subsequent
mq_open(),
will result in the failure of message queue system calls, with
errno
set to
EBADF.
If the process has a registered notification request with the message queue
associated with this
mqdes,
the registration is canceled and the queue becomes available for
another process to register a notification request.
If the message queue has been unlinked and
mqdes
is the only existing open descriptor for the queue, the queue is
destroyed.
To use this function, link in the realtime library by specifying
-lrt
on the compiler or linker command line.
RETURN VALUE
mq_close()
returns the following values:
- 0
Successful completion.
- -1
Failure.
errno
is set to indicate the error.
ERRORS
If
mq_close()
fails,
errno
is set to one of the following values:
- [EBADF]
mqdes
is not a valid message queue descriptor.
- [ENOSYS]
mq_close()
is not supported by the implementation.
STANDARDS CONFORMANCE
mq_close(): POSIX 1003.1b
