ipc_namespaces

IPC_NAMESPACES(7)          Linux Programmer's Manual         IPC_NAMESPACES(7)



NAME
       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
       This page is part of release 5.04 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



Linux                             2019-08-02                 IPC_NAMESPACES(7)