04-27-2006
Thank you Blowtorch... It seems that all that things are "implementation specific" and related to PA-RISC "strangeley" designed memory management...
man mmap() says that HP-UX may or may not call shmat() to access shared memory... of course this doesn't help me much... and says that the max shareable mem size is 1.75 GBytes. But I still don't know why I cannot go beyond 900 MB... for my posix queues.
The link you give me is related to SYS V style queues not posix queues and is probably not related to our limitations because we have already created more than 200 queues of 256 bytes length and 10 000 or 100 000 messages per queue...
Thank you again...
10 More Discussions You Might Find Interesting
1. Programming
How can I increase the POSIX Msg Q parameter SC_MQ_PRIO_MAX? The maximum is defined as 32. Can I increase the number? If so, how?
Deepa (0 Replies)
Discussion started by: Deepa
0 Replies
2. UNIX for Dummies Questions & Answers
What are the differences/similarities between posix and system V ipc and their mechanisms?
also, why is system v only limited to inter-process communication on a single node?
thanks (0 Replies)
Discussion started by: jsimpson
0 Replies
3. Linux
Hi all,
Please tell me how to change POSIX message queue maximum size? "ulimit" is not a solution because it controls shell resources. But i need to control queue size before login in and starting the shell. It is needed to limit queue size for applications started before login in.
Sorry for my... (7 Replies)
Discussion started by: Vourhey
7 Replies
4. Programming
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)
Discussion started by: mohit3884
0 Replies
5. Programming
Hi,
I´m having a lot of problems when working with message queues, both on HP-UX Systems and Sun Solaris. When we fill a queue with a messages, the system hangs and locks everything that relies on the use of IPC resources. Anyone knows how to eliminate this problem?
Thanks,
Haroldo Teixeira (2 Replies)
Discussion started by: haroldo
2 Replies
6. UNIX for Dummies Questions & Answers
Hi everybody,
this is the situation. there is a programm XYZ which opens a message queue with the key 47110815 and waits for a SIGUSR1. After receiving this signal it sends a message with type 100 and a number (as ASCII) in the message-body.
I have to write a prog which frist sends the... (1 Reply)
Discussion started by: daredevil82m
1 Replies
7. Programming
I want to have a message send & receive through 2 uni-direction FIFO
Flow of data
FIFO1
stdin--->parent(client) writefd--->FIFO1-->child(server) readfd
FIFO2
child(server) writefd2---->FIFO2--->parent(client) readfd2--->stdout
I need to have boundary structed message... (3 Replies)
Discussion started by: ouou
3 Replies
8. Programming
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)
Discussion started by: ouou
1 Replies
9. Programming
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)
Discussion started by: sumtata
1 Replies
10. Programming
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