1IPC_NAMESPACES(7)          Linux Programmer's Manual         IPC_NAMESPACES(7)
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NAME

6       namespaces - overview of Linux IPC namespaces
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DESCRIPTION

9       IPC  namespaces  isolate  certain  IPC  resources, namely, System V IPC
10       objects (see sysvipc(7)) and (since Linux 2.6.30) POSIX message  queues
11       (see  mq_overview(7)).   The  common characteristic of these IPC mecha‐
12       nisms is that IPC objects  are  identified  by  mechanisms  other  than
13       filesystem pathnames.
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15       Each  IPC namespace has its own set of System V IPC identifiers and its
16       own POSIX message queue filesystem.  Objects created in an  IPC  names‐
17       pace are visible to all other processes that are members of that names‐
18       pace, but are not visible to processes in other IPC namespaces.
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20       The following /proc interfaces are distinct in each IPC namespace:
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22       *  The POSIX message queue interfaces in /proc/sys/fs/mqueue.
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24       *  The System V IPC interfaces  in  /proc/sys/kernel,  namely:  msgmax,
25          msgmnb, msgmni, sem, shmall, shmmax, shmmni, and shm_rmid_forced.
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27       *  The System V IPC interfaces in /proc/sysvipc.
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29       When an IPC namespace is destroyed (i.e., when the last process that is
30       a member of the namespace terminates), all IPC objects in the namespace
31       are automatically destroyed.
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33       Use  of  IPC  namespaces  requires a kernel that is configured with the
34       CONFIG_IPC_NS option.
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SEE ALSO

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

41       This  page  is  part of release 5.04 of the Linux man-pages project.  A
42       description of the project, information about reporting bugs,  and  the
43       latest     version     of     this    page,    can    be    found    at
44       https://www.kernel.org/doc/man-pages/.
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48Linux                             2019-08-02                 IPC_NAMESPACES(7)
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