From 77eaf0524b54ebec917bde5c84daa9ca1d873581 Mon Sep 17 00:00:00 2001 From: Michael Kerrisk Date: Sat, 12 Aug 2017 22:45:48 +0200 Subject: [PATCH] namespaces.7: ffix Signed-off-by: Michael Kerrisk --- man7/namespaces.7 | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/man7/namespaces.7 b/man7/namespaces.7 index dd171cbba..5cb0f8f96 100644 --- a/man7/namespaces.7 +++ b/man7/namespaces.7 @@ -34,7 +34,7 @@ have their own isolated instance of the global resource. Changes to the global resource are visible to other processes that are members of the namespace, but are invisible to other processes. One use of namespaces is to implement containers. - +.PP Linux provides the following namespaces: .TS lB lB lB @@ -48,7 +48,7 @@ PID CLONE_NEWPID Process IDs User CLONE_NEWUSER User and group IDs UTS CLONE_NEWUTS Hostname and NIS domain name .TE - +.PP This page describes the various namespaces and the associated .I /proc files, and summarizes the APIs for working with namespaces. @@ -115,7 +115,7 @@ Each process has a subdirectory containing one entry for each namespace that supports being manipulated by .BR setns (2): - +.PP .in +4n .nf $ \fBls \-l /proc/$$/ns\fP @@ -130,7 +130,7 @@ lrwxrwxrwx. 1 mtk mtk 0 Apr 28 12:46 user \-> user:[4026531837] lrwxrwxrwx. 1 mtk mtk 0 Apr 28 12:46 uts \-> uts:[4026531838] .fi .in - +.PP Bind mounting (see .BR mount (2)) one of the files in this directory @@ -138,7 +138,7 @@ to somewhere else in the filesystem keeps the corresponding namespace of the process specified by .I pid alive even if all processes currently in the namespace terminate. - +.PP Opening one of the files in this directory (or a file that is bind mounted to one of these files) returns a file handle for @@ -149,7 +149,7 @@ the namespace will remain alive, even if all processes in the namespace terminate. The file descriptor can be passed to .BR setns (2). - +.PP In Linux 3.7 and earlier, these files were visible as hard links. Since Linux 3.8, .\" commit bf056bfa80596a5d14b26b17276a56a0dcb080e5 @@ -162,14 +162,14 @@ field returned by .BR stat (2). The content of this symbolic link is a string containing the namespace type and inode number as in the following example: - +.PP .in +4n .nf $ \fBreadlink /proc/$$/ns/uts\fP uts:[4026531838] .fi .in - +.PP The symbolic links in this subdirectory are as follows: .TP .IR /proc/[pid]/ns/cgroup " (since Linux 4.6)" @@ -324,13 +324,13 @@ POSIX message queues (see The common characteristic of these IPC mechanisms is that IPC objects are identified by mechanisms other than filesystem pathnames. - +.PP 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. - +.PP The following .I /proc interfaces are distinct in each IPC namespace: @@ -357,7 +357,7 @@ The System V IPC interfaces in 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. - +.PP Use of IPC namespaces requires a kernel that is configured with the .B CONFIG_IPC_NS option. @@ -379,12 +379,12 @@ A virtual network device ("veth") pair provides a pipe-like abstraction that can be used to create tunnels between network namespaces, and can be used to create a bridge to a physical network device in another namespace. - +.PP When a network namespace is freed (i.e., when the last process in the namespace terminates), its physical network devices are moved back to the initial network namespace (not to the parent of the process). - +.PP Use of network namespaces requires a kernel that is configured with the .B CONFIG_NET_NS option. @@ -421,7 +421,7 @@ and can be retrieved using .BR gethostname (2), and .BR getdomainname (2). - +.PP Use of UTS namespaces requires a kernel that is configured with the .B CONFIG_UTS_NS option.