Hi,
I am working closly with unix message queues i have encountered the following -
after creating the Q and start working with it (pushing & pulling) i receive the following stange parameters on the q's -
STIME=no_entry
Qnum=0
CBYTES=4140
when this happens, the Q is disabled (meaning i... (3 Replies)
Hi there:
Thanks first. When I use a message queue amony severl processes, will I have to synchronize the queue? I don't think I would have to because a message queue is implemented in a link listed. Correct me If I am wrong... (0 Replies)
hi all...
ive been trying this program where i spawn 4 threads... and i am trying to use message queue to send msgs from 3 of the threads to the parent thread... but it doent seem to be working... ive almost pulled out my hair tryin to fix the prob :confused:
another wierd thing... (1 Reply)
Hello,
i need to write a message queue "chat server", that should work only localy.
Can anyone please help me with some ideas and peshaps code. I'm studying the UNIX IPC mechanisms right now. So far, i understand how it works but i still cannot get an idea how to write a chat programm...
... (2 Replies)
Hii can anyone pls tell how to limit the max no of message in a posix message queue. I have made changes in proc/sys/fs/mqueue/msg_max
But still whenever i try to read the value of max. message in the queue using attr.mq_curmsgs (where struct mq_attr attr) its giving the default value as 10.... (0 Replies)
Hi all,
I need help about message queues, i have a server-client program that communicates each other via msg queue, firstly server opens its msg queue and waits for msg then client opens server msg queue and its own msg queue(for receiving msg from server,clients sends msg to server msg... (7 Replies)
Hello !!!!! I have a simple question but i can't find the answer anywhere hope to meet it here.
Why it is a bad idea to pass pointers through message queues ?
Most structs i see all of their char types are arrays... Is it becase having pointers means we could possibily send wrong bytes ?
For... (2 Replies)
Hi,
I have a dilemma.I am running denyhosts on one of our servers and it monitors illegal ssh/ftp loggins. I am running vsftpd.
My manager though has put an additional requirement on me. When someone is blocked my denyhosts he want an error message to be displayed: " YOUR ACCOUNT HAS BEEN... (0 Replies)
Discussion started by: mojoman
0 Replies
LEARN ABOUT HPUX
mq_send
mq_send(2) System Calls Manual mq_send(2)NAME
mq_send - send a message to a message queue
SYNOPSIS DESCRIPTION
The system call adds a message pointed to by the argument msg_ptr to the message queue specified by mqdes. The msg_len argument specifies
the length of the message in bytes. The value of msg_len should be less than or equal to the mq_msgsize attribute of the message queue, or
will fail.
If the specified message queue is not full, will insert the message into the queue at the position indicated by the msg_prio argument. A
message with priority, msg_prio, will be inserted behind any other messages with larger or equal priority. The value of msg_prio should be
less than
If the specified message queue is full and the flag is not set in the message queue blocking status associated with mqdes, will block in
priority order, until it can send a message on the queue, or until is interrupted by a signal. If the specified message queue is full and
the flag is set in the message queue blocking status associated with mqdes, the message will not be enqueued, and will return with an
error.
To use this function, link in the realtime library by specifying on the compiler or linker command line.
RETURN VALUE
returns the following values:
Successful completion. The message is enqueued.
Failure.
is set to indicate the error and the message is not enqueued.
ERRORS
If fails, is set to one of the following values:
[EAGAIN] The flag is set in the message queue blocking status associated with mqdes, and the message queue is full.
[EBADF] mqdes is not a valid message queue descriptor open for writing.
[EINTR] A signal interrupted the call to
[EINVAL] msg_ptr points to an invalid address, or the value of msg_prio is outside the valid range.
[EMSGSIZE] The specified message length, msg_len, exceeds the message size attribute of the message queue.
[ENOSYS] is not supported by the implementation.
SEE ALSO mq_receive(2), mq_setattr(2), mq_getattr(2), sysconf(2).
STANDARDS CONFORMANCE mq_send(2)