11-10-2010
creating a message queue using mq_open
Hi all,
First of all thanks in advance for reading my post and for your heart for helping me.
I am trying to create a message queue using mq_open(name,oflags,mode_t,attr) method. But that function call is returning with an error code EFAULT. By googling it I found that it happens when there is an invalid memory address reference and in another forum it is said that it is because of "internal virtual memory error". Can anybody please help me to get out of this error. Any efforts will be very much appreciated. I am really stuck with that..
Once again thanking you all and waiting for a reply,
regards,
paru.
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LEARN ABOUT OPENSOLARIS
mq_close
mq_close(3C) Standard C Library Functions mq_close(3C)
NAME
mq_close - close a message queue
SYNOPSIS
#include <mqueue.h>
int mq_close(mqd_t mqdes);
DESCRIPTION
The mq_close() function removes the association between the message queue descriptor, mqdes, and its message queue. The results of using
this message queue descriptor after successful return from this mq_close(), and until the return of this message queue descriptor from a
subsequent mq_open(3C), are undefined.
If the process (or thread) has successfully attached a notification request to the message queue via this mqdes, this attachment is removed
and the message queue is available for another process to attach for notification.
RETURN VALUES
Upon successful completion, mq_close() returns 0; otherwise, the function returns -1 and sets errno to indicate the error condition.
ERRORS
The mq_close() function will fail if:
EBADF The mqdes argument is an invalid message queue descriptor.
ENOSYS The mq_open() function is not supported by the system.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
|ATTRIBUTE TYPE |ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Committed |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
|Standard |See standards(5). |
+-----------------------------+-----------------------------+
SEE ALSO
mqueue.h(3HEAD), mq_notify(3C), mq_open(3C), mq_unlink(3C), attributes(5), standards(5)
NOTES
Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned
-1 and set errno to ENOSYS.
SunOS 5.11 5 Feb 2008 mq_close(3C)