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Diffstat (limited to 'man5/proc_pid_root.5')
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diff --git a/man5/proc_pid_root.5 b/man5/proc_pid_root.5 deleted file mode 100644 index 5263329..0000000 --- a/man5/proc_pid_root.5 +++ /dev/null @@ -1,75 +0,0 @@ -.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com> -.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com> -.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org> -.\" -.\" SPDX-License-Identifier: GPL-3.0-or-later -.\" -.TH proc_pid_root 5 2023-08-15 "Linux man-pages 6.7" -.SH NAME -/proc/pid/root/ \- symbolic link to root directory -.SH DESCRIPTION -.TP -.IR /proc/ pid /root/ -UNIX and Linux support the idea of a per-process root of the -filesystem, set by the -.BR chroot (2) -system call. -This file is a symbolic link that points to the process's -root directory, and behaves in the same way as -.IR exe , -and -.IR fd/* . -.IP -Note however that this file is not merely a symbolic link. -It provides the same view of the filesystem (including namespaces and the -set of per-process mounts) as the process itself. -An example illustrates this point. -In one terminal, we start a shell in new user and mount namespaces, -and in that shell we create some new mounts: -.IP -.in +4n -.EX -$ \fBPS1=\[aq]sh1# \[aq] unshare \-Urnm\fP -sh1# \fBmount \-t tmpfs tmpfs /etc\fP # Mount empty tmpfs at /etc -sh1# \fBmount \-\-bind /usr /dev\fP # Mount /usr at /dev -sh1# \fBecho $$\fP -27123 -.EE -.in -.IP -In a second terminal window, in the initial mount namespace, -we look at the contents of the corresponding mounts in -the initial and new namespaces: -.IP -.in +4n -.EX -$ \fBPS1=\[aq]sh2# \[aq] sudo sh\fP -sh2# \fBls /etc | wc \-l\fP # In initial NS -309 -sh2# \fBls /proc/27123/root/etc | wc \-l\fP # /etc in other NS -0 # The empty tmpfs dir -sh2# \fBls /dev | wc \-l\fP # In initial NS -205 -sh2# \fBls /proc/27123/root/dev | wc \-l\fP # /dev in other NS -11 # Actually bind - # mounted to /usr -sh2# \fBls /usr | wc \-l\fP # /usr in initial NS -11 -.EE -.in -.IP -.\" The following was still true as at kernel 2.6.13 -In a multithreaded process, the contents of the -.IR /proc/ pid /root -symbolic link are not available if the main thread has already terminated -(typically by calling -.BR pthread_exit (3)). -.IP -Permission to dereference or read -.RB ( readlink (2)) -this symbolic link is governed by a ptrace access mode -.B PTRACE_MODE_READ_FSCREDS -check; see -.BR ptrace (2). -.SH SEE ALSO -.BR proc (5) |