1IPC_NAMESPACES(7) Linux Programmer's Manual IPC_NAMESPACES(7)
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6 ipc_namespaces - overview of Linux IPC namespaces
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9 IPC namespaces isolate certain IPC resources, namely, System V IPC ob‐
10 jects (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 name‐
17 space are visible to all other processes that are members of that name‐
18 space, 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, ms‐
25 gmnb, 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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37 nsenter(1), unshare(1), clone(2), setns(2), unshare(2), mq_overview(7),
38 namespaces(7), sysvipc(7)
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41 This page is part of release 5.10 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)