06-17-2004
error mq_open message queue
Hello,
J work on a HP.
I want to create message queue by using mq_open with this parameters:
mq_open(p,O_CREAT|O_WRONLY|O_EXCL|0_NONBLOCK,0600,&queue_attr)
with p char [][]
and the function returns the value -1 and errno equal 2.
can you help me ?
Thank.
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LEARN ABOUT SUNOS
mq_unlink
mq_unlink(3RT) mq_unlink(3RT)
NAME
mq_unlink - remove a message queue
SYNOPSIS
cc [ flag... ] file... -lrt [ library... ]
#include <mqueue.h>
int mq_unlink(const char *name);
The mq_unlink() function removes the message queue named by the pathname name. After a successful call to mq_unlink() with name, a call to
mq_open(3RT) with name fails 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 is postponed until all references to the message queue have been closed. Calls to mq_open(3RT)
to re-create 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, mq_unlink() returns 0; otherwise, the named message queue is not changed by this function call, the function
returns -1 and sets errno to indicate the error.
The mq_unlink() function will fail if:
EACCES Permission is denied to unlink the named message queue.
ENAMETOOLONG The length of the name string exceeds PATH_MAX, or a pathname component is longer than NAME_MAX while
_POSIX_NO_TRUNC is in effect.
ENOENT The named message queue, name, does not exist.
ENOSYS mq_unlink() is not supported by the system.
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
mqueue.h(3HEAD), mq_close(3RT), mq_open(3RT), attributes(5), standards(5)
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.
28 Jun 2002 mq_unlink(3RT)