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IPCS(1)                     General Commands Manual                    IPCS(1)

NAME
     ipcs - report System V interprocess communication facilities status

SYNOPSIS
     ipcs [-abcmopqstMQST]

DESCRIPTION
     The ipcs program 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
             control 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.

     -M      Display system information about shared memory.

     -Q      Display system information about messages queues.

     -S      Display system information about semaphores.

     -T      Display system information about shared memory, message queues
             and semaphores.  (This is shorthand for specifying the -M, -Q,
             and -S options.)

     If none of the -M, -m, -Q, -q, -S, -s, or -T 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.

SEE ALSO
     ipcrm(1), shmat(2), shmctl(2), shmdt(2), shmget(2)

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.

NetBSD 10.99                     June 11, 2014                    NetBSD 10.99