IPC_NAMESPACES(7) Linux Programmer's Manual IPC_NAMESPACES(7)
NAME
ipc_namespaces - overview of Linux IPC namespaces
DESCRIPTION
IPC namespaces isolate certain IPC resources, namely, System V IPC ob-
jects (see sysvipc(7)) and (since Linux 2.6.30) POSIX message queues
(see mq_overview(7)). The common characteristic of these IPC mecha-
nisms 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 name-
space are visible to all other processes that are members of that name-
space, 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, ms-
gmnb, 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 5.07 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)