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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() and msgrcv() operations on message  queues,
          the  time  of  the last shmat() and shmdt() operations on shared
          memory,  and  the  time  of  the  last  semop()   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

   ipcrm(1),   ipcmk(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 ftp://ftp.kernel.org/pub/linux/utils/util-
   linux/.



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