QNX Developer Support
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mq_close()
Close a message queue
Synopsis:
#include <mqueue.h> int mq_close( mqd_t mqdes );
Arguments:
- mqdes
- The message-queue descriptor, returned by mq_open(), of the message queue that you want to close.
Library:
- For the traditional implementation, libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
- For the alternate implementation using asynchronous messages,
libmq
Use the -l mq option to qcc to link against this library.
Description:
The mq_close() function removes the association between mqdes and a message queue. If the current process attaches a notify to this queue for notification, the attachment is eliminated. If this queue is unlinked before the call to mq_close(), and this process is the last process to call mq_close() on the queue, then the queue is destroyed, along with its contents.
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Neutrino supports two implementations of message queues: a traditional implementation, and an alternate one that uses asynchronous messages. For more information, see the entry for mq and mqueue in the Utilities Reference. |
In the traditional (mqueue) implementation, calling close() with mqdes has the same effect as calling mq_close().
Returns:
-1 if an error occurred (errno is set). Any other value indicates success.
Errors:
- EBADF
- Invalid queue mqdes.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | No |
| Thread | Yes |
See also:
mq, mqueue in the Utilities Reference
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