|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CONFORMING TO | NOTES | AUTHORS | SEE ALSO | REPORTING BUGS | AVAILABILITY |
|
|
|
IPCS(1) User Commands IPCS(1)
ipcs - show information on IPC facilities
ipcs [options]
ipcs shows information on System V inter-process communication
facilities. By default it shows information about all three
resources: shared memory segments, message queues, and semaphore
arrays.
-i, --id id
Show full details on just the one resource element identified
by id. This option needs to be combined with one of the three
resource options: -m, -q or -s.
-h, --help
Display help text and exit.
-V, --version
Print version and exit.
Resource options
-m, --shmems
Write information about active shared memory segments.
-q, --queues
Write information about active message queues.
-s, --semaphores
Write information about active semaphore sets.
-a, --all
Write information about all three resources (default).
Output formats
Of these options only one takes effect: the last one specified.
-c, --creator
Show creator and owner.
-l, --limits
Show resource limits.
-p, --pid
Show PIDs of creator and last operator.
-t, --time
Write time information. The time of the last control
operation that changed the access permissions for all
facilities, the time of the last msgsnd(2) and msgrcv(2)
operations on message queues, the time of the last shmat(2)
and shmdt(2) operations on shared memory, and the time of the
last semop(2) operation on semaphores.
-u, --summary
Show status summary.
Representation
These affect only the -l (--limits) option.
-b, --bytes
Print the sizes in bytes rather than in a human-readable
format.
By default, the unit, sizes are expressed in, is byte, and
unit prefixes are in power of 2^10 (1024). Abbreviations of
symbols are exhibited truncated in order to reach a better
readability, by exhibiting alone the first letter of them;
examples: "1 KiB" and "1 MiB" are respectively exhibited as
"1 K" and "1 M", then omitting on purpose the mention "iB",
which is part of these abbreviations.
--human
Print sizes in human-readable format.
The Linux ipcs utility is not fully compatible to the POSIX ipcs
utility. The Linux version does not support the POSIX -a, -b and
-o options, but does support the -l and -u options not defined by
POSIX. A portable application shall not use the -a, -b, -o, -l,
and -u options.
The current implementation of ipcs obtains information about
available IPC resources by parsing the files in /proc/sysvipc.
Before util-linux version v2.23, an alternate mechanism was used:
the IPC_STAT command of msgctl(2), semctl(2), and shmctl(2). This
mechanism is also used in later util-linux versions in the case
where /proc is unavailable. A limitation of the IPC_STAT
mechanism is that it can only be used to retrieve information
about IPC resources for which the user has read permission.
Krishna Balasubramanian <[email protected]>
ipcmk(1), ipcrm(1), msgrcv(2), msgsnd(2), semget(2), semop(2),
shmat(2), shmdt(2), shmget(2), sysvipc(7)
For bug reports, use the issue tracker at
https://github.com/util-linux/util-linux/issues.
The ipcs command is part of the util-linux package which can be
downloaded from Linux Kernel Archive
<https://www.kernel.org/pub/linux/utils/util-linux/>. This page
is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have
a bug report for this manual page, send it to
[email protected]. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2024-06-14. (At that time, the date of the most recent commit
that was found in the repository was 2024-06-10.) If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page,
or you have corrections or improvements to the information in
this COLOPHON (which is not part of the original manual page),
send a mail to [email protected]
util-linux 2.39.594-1e0ad 2023-07-19 IPCS(1)
Pages that refer to this page: ipcmk(1), ipcrm(1), lsipc(1), msgctl(2), semctl(2), semget(2), shmctl(2), proc_sysvipc(5), sysvipc(7)
|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|