ipcs
====

::

   NAME
     ipcs - System V IPC facilities

   SYNOPSIS
     ipcs [-smMq] [-n pid|task] [id | addr]

   DESCRIPTION
     This command provides information on the System V IPC facilities.  With no
     arguments, the command will display kernel usage of all three facilities.

          -s  show semaphore arrays.
          -m  show shared memory segments.
          -M  show shared memory segments with additional details.
          -q  show message queues.
          id  show the data associated with this resource ID.
        addr  show the data associated with this virtual address of a
              shmid_kernel, sem_array or msq_queue.

     For kernels supporting namespaces, the -n option may be used to
     display the IPC facilities with respect to the namespace of a
     specified task:

     -n pid   a process PID.
     -n task  a hexadecimal task_struct pointer.

   EXAMPLES
     Display all IPC facilities:

       crash> ipcs
       SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
       ffff880473a28310 00000000 0          0     666   90000      1       
       ffff880473a28490 00000001 32769      0     666   90000      1       
       ffff880473a28250 00000002 65538      0     666   90000      1       

       SEM_ARRAY        KEY      SEMID      UID   PERMS NSEMS     
       ffff88047200f9d0 00000000 0          0     600   1         
       ffff88046f826910 00000000 32769      0     600   1         

       MSG_QUEUE        KEY      MSQID      UID   PERMS USED-BYTES   MESSAGES
       ffff8100036bb8d0 000079d7 0          3369  666   16640        104
       ffff8100036bb3d0 000079d8 32769      3369  666   12960        81
       ffff810026d751d0 000079d9 65538      3369  666   10880        68

     Display shared memory usage with detailed information:

       crash> ipcs -M
       SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
       ffff880473a28310 00000000 0          0     666   90000      1       
       PAGES ALLOCATED/RESIDENT/SWAPPED: 22/1/0
       INODE: ffff88047239cd98

       SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
       ffff880473a28490 00000001 32769      0     666   90000      1       
       PAGES ALLOCATED/RESIDENT/SWAPPED: 22/1/0
       INODE: ffff88047239c118

       SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
       ffff880473a28250 00000002 65538      0     666   90000      1       
       PAGES ALLOCATED/RESIDENT/SWAPPED: 22/1/0
       INODE: ffff880470503758

     Display the shared memory data associated with shmid_kernel ffff880473a28250:

       crash> ipcs -M ffff880473a28250
       SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
       ffff880473a28250 00000002 65538      0     666   90000      1       
       PAGES ALLOCATED/RESIDENT/SWAPPED: 22/1/0
       INODE: ffff880470503758