11-23-2008
10 More Discussions You Might Find Interesting
1. UNIX for Advanced & Expert Users
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)
Discussion started by: kel
3 Replies
2. Programming
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)
Discussion started by: yanhu
0 Replies
3. Programming
Is there any way one can delete , say , a particular message from a message queue on system V? (2 Replies)
Discussion started by: satansfury
2 Replies
4. Programming
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)
Discussion started by: etenv
2 Replies
5. 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
6. Programming
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)
Discussion started by: SaTYR
7 Replies
7. Programming
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)
Discussion started by: qlyine
2 Replies
8. Ubuntu
Hello
How can I see the created message queues in the system? (4 Replies)
Discussion started by: xyzt
4 Replies
9. Filesystems, Disks and Memory
Hello,
On 4/20/2018, we performed a disk replacement on our IBM 8202 P7 server. After the disk was rebuilt, the SAS Disk Array sissas0 showed a status of degraded. However, the pdisks in the array all show a status of active.
We did see a message in errpt. DISK ARRAY PROTECTION SUSPENDED.
... (1 Reply)
Discussion started by: terrya
1 Replies
10. AIX
Hello,
On 4/20/2018, we performed a disk replacement on our IBM 8202 P7 server. After the disk was rebuilt, the SAS Disk Array sissas0 showed a status of degraded. However, the pdisks in the array all show a status of active.
We did see a message in errpt. DISK ARRAY PROTECTION SUSPENDED.
... (3 Replies)
Discussion started by: terrya
3 Replies
IPCRM(1) User Commands IPCRM(1)
NAME
ipcrm - remove a message queue, semaphore set or shared memory id
SYNOPSIS
ipcrm [options]
ipcrm {shm|msg|sem} id...
DESCRIPTION
ipcrm removes System V interprocess communication (IPC) objects and associated data structures from the system. In order to delete such
objects, you must be superuser, or the creator or owner of the object.
System V IPC objects are of three types: shared memory, message queues, and semaphores. Deletion of a message queue or semaphore object is
immediate (regardless of whether any process still holds an IPC identifier for the object). A shared memory object is only removed after
all currently attached processes have detached (shmdt(2)) the object from their virtual address space.
Two syntax styles are supported. The old Linux historical syntax specifies a three letter keyword indicating which class of object is to
be deleted, followed by one or more IPC identifiers for objects of this type.
The SUS-compliant syntax allows the specification of zero or more objects of all three types in a single command line, with objects speci-
fied either by key or by identifier. (See below.) Both keys and identifiers may be specified in decimal, hexadecimal (specified with an
initial '0x' or '0X'), or octal (specified with an initial '0').
OPTIONS
-M, --shmem-key shmkey
removes the shared memorysegment created with shmkey after the last detach is performed.
-m, --shmem-id shmid
removes the shared memory segment identified by shmid after the last detach is performed.
-Q, --queue-key msgkey
removes the message queue created with msgkey.
-q, --queue-id msgid
removes the message queue identified by msgid.
-S, --semaphore-key semkey
removes the semaphore created with semkey.
-s, --semaphore-id semid
removes the semaphore identified by semid.
-a, --all [shm msg sem]
Remove all resources. When option argument is provided the removal is performed only to for the specified resource types. Warning!
Do not use -a if you are unsure how the software using resources might react on missing objects. Some programs create these
resources at start up and may not have any code to deal unexpected disappearance.
The details of the removes are described in msgctl(2), shmctl(2), and semctl(2). The identifiers and keys may be found by using ipcs(1).
NOTES
In its first Linux implementation, ipcrm used the deprecated syntax shown in the SYNOPSIS. Functionality present in other *nix implementa-
tions of ipcrm has since been added, namely the ability to delete resources by key (not just identifier), and to respect the same command-
line syntax. For backward compatibility the previous syntax is still supported.
SEE ALSO
ipcs(1), ipcmk(1), msgctl(2), msgget(2), semctl(2), semget(2), shmctl(2), shmdt(2), shmget(2), ftok(3)
AVAILABILITY
The ipcrm command is part of the util-linux package and is available from Linux Kernel Archive <ftp://ftp.kernel.org/pub/linux/utils/util-
linux/>.
util-linux September 2011 IPCRM(1)