NAME

       ipc_namespaces - overview of Linux IPC namespaces

DESCRIPTION

       IPC  namespaces  isolate  certain IPC resources, namely, System V IPC objects (see sysvipc(7)) and (since
       Linux 2.6.30) POSIX message  queues  (see  mq_overview(7)).   The  common  characteristic  of  these  IPC
       mechanisms is that IPC objects are identified by mechanisms other than filesystem pathnames.

       Each  IPC  namespace  has  its  own  set  of  System  V  IPC  identifiers and its own POSIX message queue
       filesystem.  Objects created in an IPC namespace are visible to all other processes that are  members  of
       that namespace, but are not visible to processes in other IPC namespaces.

       The following /proc interfaces are distinct in each IPC namespace:

       *  The POSIX message queue interfaces in /proc/sys/fs/mqueue.

       *  The  System V IPC interfaces in /proc/sys/kernel, namely: msgmax, msgmnb, msgmni, sem, shmall, shmmax,
          shmmni, and shm_rmid_forced.

       *  The System V IPC interfaces in /proc/sysvipc.

       When an IPC namespace is destroyed (i.e., when the last  process  that  is  a  member  of  the  namespace
       terminates), all IPC objects in the namespace are automatically destroyed.

       Use of IPC namespaces requires a kernel that is configured with the CONFIG_IPC_NS option.

SEE ALSO

       nsenter(1), unshare(1), clone(2), setns(2), unshare(2), mq_overview(7), namespaces(7), sysvipc(7)

COLOPHON

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       https://www.kernel.org/doc/man-pages/.