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ipcs(1) [freebsd man page]

IPCS(1) 						    BSD General Commands Manual 						   IPCS(1)

NAME
ipcs -- report System V interprocess communication facilities status SYNOPSIS
ipcs [-abcmopqstMQSTy] [-C core] [-N system] [-u user] DESCRIPTION
The ipcs utility provides information on System V interprocess communication (IPC) facilities on the system. The options are as follows: -a Show the maximum amount of information possible when displaying active semaphores, message queues, and shared memory segments. (This is shorthand for specifying the -b, -c, -o, -p, and -t options.) -b Show the maximum allowed sizes for active semaphores, message queues, and shared memory segments. The ``maximum allowed size'' is the maximum number of bytes in a message on a message queue, the size of a shared memory segment, or the number of semaphores in a set of semaphores. -c Show the creator's name and group for active semaphores, message queues, and shared memory segments. -m Display information about active shared memory segments. -o Show outstanding usage for active message queues, and shared memory segments. The ``outstanding usage'' is the number of messages in a message queue, or the number of processes attached to a shared memory segment. -p Show the process ID information for active semaphores, message queues, and shared memory segments. The ``process ID information'' is the last process to send a message to or receive a message from a message queue, the process that created a semaphore, or the last process to attach or detach a shared memory segment. -q Display information about active message queues. -s Display information about active semaphores. -t Show access times for active semaphores, message queues, and shared memory segments. The access times is the time of the last con- trol operation on an IPC object, the last send or receive of a message, the last attach or detach of a shared memory segment, or the last operation on a semaphore. -C core Extract values associated with the name list from the specified core instead of the default /dev/kmem. Implies -y. -M Display system information about shared memory. -N system Extract the name list from the specified system instead of the default /boot/kernel/kernel. Implies -y. -Q Display system information about messages queues. -S Display system information about semaphores. -T Display system information about shared memory, message queues and semaphores. -y Use the kvm(3) interface instead of the sysctl(3) interface to extract the required information. If ipcs is to operate on the run- ning system, using kvm(3) will require read privileges to /dev/kmem. -u user Display information about IPC mechanisms owned by user. User specification can be in the form of a numeric UID or a login name. If none of the -M, -m, -Q, -q, -S, or -s options are specified, information about all active IPC facilities is listed. RESTRICTIONS
System data structures may change while ipcs is running; the output of ipcs is not guaranteed to be consistent. FILES
/dev/kmem default kernel memory /boot/kernel/kernel default system name list SEE ALSO
ipcrm(1) AUTHORS
Thorsten Lockert <tholo@sigmasoft.com> BUGS
This manual page is woefully incomplete, because it does not at all attempt to explain the information printed by ipcs. BSD
March 24, 2004 BSD

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IPCS(1) 							   User Commands							   IPCS(1)

NAME
ipcs - show information on IPC facilities SYNOPSIS
ipcs [options] DESCRIPTION
ipcs shows information on the inter-process communication facilities for which the calling process has read access. By default it shows information about all three resources: shared memory segments, message queues, and semaphore arrays. OPTIONS
-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 Display version information 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 mem- ory, 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 sizes in bytes. --human Print sizes in human-readable format. SEE ALSO
ipcmk(1), ipcrm(1), msgrcv(2), msgsnd(2), semget(2), semop(2), shmat(2), shmdt(2), shmget(2) CONFORMING TO
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. AUTHOR
Krishna Balasubramanian <balasub@cis.ohio-state.edu> AVAILABILITY
The ipcs command is part of the util-linux package and is available from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils/util- linux/>. util-linux July 2014 IPCS(1)
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