ipc_namespaces(7) - Linux manual page (original) (raw)

ipcnamespaces(7) Miscellaneous Information Manual ipcnamespaces(7)

NAME top

   ipc_namespaces - overview of Linux IPC namespaces

DESCRIPTION top

   IPC namespaces isolate certain IPC resources, namely, System V IPC
   objects (see [sysvipc(7)](../man7/sysvipc.7.html)) and (since Linux 2.6.30) POSIX message
   queues (see [mq_overview(7)](../man7/mq%5Foverview.7.html)).  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
      _shmrmidforced_.

   •  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 top

   [nsenter(1)](../man1/nsenter.1.html), [unshare(1)](../man1/unshare.1.html), [clone(2)](../man2/clone.2.html), [setns(2)](../man2/setns.2.html), [unshare(2)](../man2/unshare.2.html),
   [mq_overview(7)](../man7/mq%5Foverview.7.html), [namespaces(7)](../man7/namespaces.7.html), [sysvipc(7)](../man7/sysvipc.7.html)

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Linux man-pages 6.10 2024-05-02 ipcnamespaces(7)

Pages that refer to this page:nsenter(1), unshare(1), clone(2), lttng-ust(3), systemd.exec(5), mq_overview(7), namespaces(7), sysvipc(7)