Right?
What if the applications must be run by init-scripts? So...
Is there any kernel options to specify POSIX queue size?
I found information about /proc/sys/fs/mqueue/. But there are no files to specify queue size. Only message size, messages count and queues count.
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)
Hello,
My question is related to "pipcs -qa" command under HP-UX 11i PA-RISC 64 bits.
We have a little C program that creates posix ipc message queues using the mq_open() system function.
The program fail with 'No space left on device' error when we create big queues. What is the system... (6 Replies)
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 am trying to implement posix message queue application. I am faced with an error on the mq_receive section. It says "Message too long". I've tried couple of small tweeks, but to no result. Please do suggest any rectificaitons.
mq_send section-works successfully
#include... (2 Replies)
in a single main() function,so need signal handling. Use Posix Message Queue IPC mechanism , can ignore the priority and other linked list message,to implement the scenario:
client:Knock Knock
server:who's there
client: Eric
Server:Eric,Welcome.
client:exit
all process terminated
... (1 Reply)
Hi,
I wanted to know whether the POSIX message queues are statically allocated memory by the kernel based on the parameters specified in the open or as and when we send messages, memory are allocated?
Does the kernel reserve the specified memory for the message queue irrespective of whether... (1 Reply)
hello, I try to test the POSIX mq_open function on book unp like below:
#include "unpipc.h"
# include <mqueue.h>
int main(int argc, char **argv)
{
int c, flags;
mqd_t mqd;
flags = O_RDWR | O_CREAT;
while ((c = getopt(argc, argv, "e")) != -1) {
... (3 Replies)
Discussion started by: anpufeng
3 Replies
LEARN ABOUT PHP
mq_unlink
MQ_UNLINK(3) Linux Programmer's Manual MQ_UNLINK(3)NAME
mq_unlink - remove a message queue
SYNOPSIS
#include <mqueue.h>
int mq_unlink(const char *name);
Link with -lrt.
DESCRIPTION
mq_unlink() removes the specified message queue name. The message queue name is removed immediately. The queue itself is destroyed once
any other processes that have the queue open close their descriptors referring to the queue.
RETURN VALUE
On success mq_unlink() returns 0; on error, -1 is returned, with errno set to indicate the error.
ERRORS
EACCES The caller does not have permission to unlink this message queue.
ENAMETOOLONG
name was too long.
ENOENT There is no message queue with the given name.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+------------+---------------+---------+
|Interface | Attribute | Value |
+------------+---------------+---------+
|mq_unlink() | Thread safety | MT-Safe |
+------------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
SEE ALSO mq_close(3), mq_getattr(3), mq_notify(3), mq_open(3), mq_receive(3), mq_send(3), mq_overview(7)COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
Linux 2015-08-08 MQ_UNLINK(3)