<systemitem>procps</systemitem> package contains several utilities
that use it.
</para>
+ <refentry id="proc">
+ <!-- based on Linux manpages project proc(5)
+ (c) Copyright 2020 Cygwin project
+ (c) Copyright 2002\-2008,2017 Michael Kerrisk <mtk.manpages@gmail.com>
+ (c) Copyright 1994, 1995 by Daniel Quinlan (quinlan@yggdrasil.com) -->
+
+ <!-- %%%LICENSE_START(GPLv2+_DOC_FULL)
+ This is free documentation; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of
+ the License, or (at your option) any later version. -->
+
+ <!-- The GNU General Public License's references to "object code"
+ and "executables" are to be interpreted as the output of any
+ document formatting or typesetting system, including
+ intermediate and printed output. -->
+
+ <!-- This manual is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details. -->
+
+ <!-- You should have received a copy of the GNU General Public
+ License along with this manual; if not, see
+ <<ulink url='http://www.gnu.org/licenses/>'>http://www.gnu.org/licenses/></ulink>.
+ %%%LICENSE_END -->
+
+ <refentryinfo>
+ <date>2020-11-24</date>
+ <author>Cygwin Project</author>
+ </refentryinfo>
+ <refmeta>
+ <refentrytitle>proc</refentrytitle>
+ <manvolnum>5</manvolnum>
+ <refmiscinfo class='date'>2020-11-24</refmiscinfo>
+ <refmiscinfo class='source'>Cygwin</refmiscinfo>
+ <refmiscinfo class='manual'>Cygwin User's Manual</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+ <refname>proc</refname>
+ <refpurpose>process and system information pseudo-filesystem</refpurpose>
+ </refnamediv>
+
+ <refsect1 id='proc-desc'>
+ <title>Description</title>
+ <para>The <filename>proc</filename> filesystem is a pseudo-filesystem
+ which provides an interface to Cygwin data structures.
+ It is commonly mounted at <filename>/proc</filename>.
+ Typically, it is mounted automatically by the system.
+ </para>
+
+ <refsect2 id='proc-overview'>
+ <title>Overview</title>
+ <para>Underneath <filename>/proc</filename>, there are the following
+ general groups of files and subdirectories:
+ </para>
+
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename> subdirectories</term>
+ <listitem>
+ <para>Each one of these subdirectories contains files and
+ subdirectories exposing information about the process with the
+ corresponding process id.
+ </para>
+
+ <para>The <filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename> subdirectories are
+ visible when iterating through <filename>/proc</filename> with
+ <citerefentry>
+ <refentrytitle>readdir</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>
+ (and thus are visible when one uses
+ <citerefentry>
+ <refentrytitle>ls</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>
+ to view the contents of <filename>/proc</filename>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/self</filename></term>
+ <listitem>
+ <para>When a process accesses this magic symbolic link, it resolves
+ to the process's own <filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename> directory.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[a-z]*</emphasis></filename></term>
+ <listitem>
+ <para>Various other files and subdirectories under
+ <filename>/proc</filename> expose system-wide information.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ <para>All of the above are described in more detail below.
+ </para>
+
+ </refsect2>
+
+ <refsect2 id='proc-files-and-directories'>
+ <title>Files and directories</title>
+ <para>
+ The following list provides details of many of the files
+ and directories under the <filename>/proc</filename> hierarchy.
+ </para>
+
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename></term>
+ <listitem>
+ <para>
+ There is a numerical subdirectory for each running
+ process; the subdirectory is named by the process id.
+ Each <filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename> subdirectory
+ contains the pseudo-files and directories described below.
+ </para>
+
+ <para>The files inside each <filename>/proc/<emphasis remap='I'>[pid]</emphasis></filename>
+ directory are normally owned by the effective user and
+ effective group id of the process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/cmdline</filename></term>
+ <listitem>
+ <para>This read-only file holds the complete command line for the
+ process, unless the process is a zombie.
+ In the latter case, there is nothing in this file: that is, a
+ read on this file will return 0 characters.
+ The command-line arguments appear in this file as a set of
+ strings followed by null bytes ('\0').
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/ctty</filename></term>
+ <listitem>
+ <para>
+ This read-only file holds the name of the console or control
+ terminal device for the process, unless the process is detached
+ from any terminal.
+ In the latter case, there is only a newline in this file.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/cwd</filename></term>
+ <listitem>
+ <para>
+ This is a symbolic link to the current working directory of the
+ process.
+ To find out the current working directory of process 20, for
+ instance, you can do this:
+
+ <screen>
+ <prompt>$</prompt> <userinput>cd /proc/20/cwd; /bin/pwd</userinput>
+ </screen>
+ </para>
+
+ <para>Note that the <emphasis remap='I'>pwd</emphasis> command
+ is often a shell built-in, and might not work properly. In
+ <citerefentry>
+ <refentrytitle>bash</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ you may use <userinput>pwd -P</userinput>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/environ</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the current environment that may
+ have been changed by the currently executing program.
+ The entries are separated by null bytes ('\0'),
+ and there may be a null byte at the end.
+ Thus, to print out the environment of process 1, you would do:
+
+ <screen>
+ <prompt>$</prompt> <userinput>cat -A /proc/1/environ</userinput>
+ </screen>
+ </para>
+
+ <para>If, after an
+ <citerefentry>
+ <refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>,
+ the process modifies its environment (e.g., by calling
+ functions such as
+ <citerefentry>
+ <refentrytitle>putenv</refentrytitle><manvolnum>3</manvolnum>
+ </citerefentry>
+ or modifying the
+ <citerefentry>
+ <refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>
+ variable directly), this file will reflect those changes.
+ That may not be the case on other systems such as Linux.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/exe</filename></term>
+ <listitem>
+ <para>
+ This file is a symbolic link containing the actual pathname of
+ the executed command.
+ This symbolic link can be dereferenced normally; attempting to
+ open it will open the executable.
+ You can even type <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/exe</filename>
+ to run another copy of the same executable that is being run by
+ process <emphasis remap='I'>[pid]</emphasis>.
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/exe</filename> is a pointer to
+ the binary which was executed, and appears as a symbolic link.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/exename</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the actual pathname of the executed
+ command.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/fd/</filename></term>
+ <listitem>
+ <para>
+ This is a subdirectory containing one entry for each
+ file which the process has open, named by its file
+ descriptor, and which is a symbolic link to the actual
+ file.
+ Thus, 0 is standard input, 1 standard output, 2 standard
+ error, and so on.
+ </para>
+
+ <para>
+ For file descriptors for pipes and sockets, the entries will
+ be symbolic links whose content is the file type with the
+ inode. A
+ <citerefentry>
+ <refentrytitle>readlink</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>
+ call on this file returns a string in the format:
+ <literal>type:<emphasis remap='I'>[inode]</emphasis></literal>
+ </para>
+
+ <para>For example, <literal>socket:[2248868]</literal>
+ will be a socket and its inode is 2248868.
+ </para>
+
+ <para>
+ Programs that take a filename as a command-line argument, but
+ don't take input from standard input if no argument is supplied,
+ and programs that write to a file named as a command-line
+ argument, but don't send their output to standard output if no
+ argument is supplied, can nevertheless be made to use standard
+ input or standard output by using
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/fd</filename> files as command-line
+ arguments.
+ For example, assuming that <option>-i</option> is the flag
+ designating an input file and <option>-o</option> is the flag
+ designating an output file:
+
+ <screen>
+ <prompt>$</prompt> <userinput>foobar -i /proc/self/fd/0 -o /proc/self/fd/1 ...</userinput>
+ </screen>
+
+ and you have a working filter.
+ </para>
+
+ <para><filename>/proc/self/fd/N</filename> is approximately
+ the same as <filename>/dev/fd/N</filename> in some Unix
+ and Unix-like systems.
+ Most Linux <command>makedev</command> scripts symbolically
+ link <filename>/dev/fd</filename> to
+ <filename>/proc/self/fd</filename>, in fact.
+ </para>
+
+ <para>Most systems provide symbolic links
+ <filename>/dev/stdin</filename>,
+ <filename>/dev/stdout</filename>, and
+ <filename>/dev/stderr</filename>, which respectively link
+ to the files <literal>0</literal>, <literal>1</literal>,
+ and <literal>2</literal> in <filename>/proc/self/fd</filename>.
+ Thus the example command above could be written as:
+
+ <screen>
+ <prompt>$</prompt> <userinput>foobar -i /dev/stdin -o /dev/stdout ...</userinput>
+ </screen>
+ </para>
+
+ <para>
+ Note that for file descriptors referring to inodes (pipes and
+ sockets, see above), those inodes still have permission bits and
+ ownership information distinct from those of the
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/fd</filename> entry, and that the
+ owner may differ from the user and group ids of the process.
+ An unprivileged process may lack permissions to open them, as in
+ this example:
+
+ <screen>
+ <prompt>$</prompt> <userinput>echo test | sudo -u nobody cat</userinput>
+ <computeroutput>test</computeroutput>
+ <prompt>$</prompt> <userinput>echo test | sudo -u nobody cat /proc/self/fd/0</userinput>
+ <computeroutput>cat: /proc/self/fd/0: Permission denied</computeroutput>
+ </screen>
+ </para>
+
+ <para>
+ File descriptor 0 refers to the pipe created by the shell and
+ owned by that shell's user, which is not
+ <literal>nobody</literal>, so <command>cat</command>
+ does not have permission to create a new file descriptor to
+ read from that inode, even though it can still read from its
+ existing file descriptor 0.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/gid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the primary group id for the
+ process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/maps</filename></term>
+ <listitem>
+ <para>
+ A file containing the currently mapped memory regions and their
+ access permissions. See
+ <citerefentry>
+ <refentrytitle>mmap</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>
+ for some further information about memory mappings.
+ </para>
+
+ <para>The format of the file is:
+
+<screen>
+<emphasis remap='I'>address perms offset dev inode pathname</emphasis>
+<computeroutput>
+00010000-00020000 rw-s 00000000 0000:0000 0 [win heap 1 default shared]
+...
+00080000-00082000 rw-p 00000000 0000:0000 0 [win heap 0 default grow]
+00082000-0009A000 ===p 00002000 0000:0000 0 [win heap 0 default grow]
+000A0000-000A1000 rw-p 00000000 0000:0000 0 [win heap 2 grow]
+000A1000-000BA000 ===p 00001000 0000:0000 0 [win heap 2 grow]
+000C0000-000D9000 rw-p 00000000 0000:0000 0 [win heap 0 default grow]
+000D9000-001C0000 ===p 00019000 0000:0000 0 [win heap 0 default grow]
+00200000-00377000 ===p 00000000 0000:0000 0
+00377000-00378000 rw-p 00177000 0000:0000 0 [peb]
+00378000-0037A000 rw-p 00178000 0000:0000 0 [teb (tid 8844)]
+...
+00400000-005F9000 ===p 00000000 0000:0000 0 [stack (tid 8884)]
+005F9000-005FC000 rw-g 001F9000 0000:0000 0 [stack (tid 8884)]
+005FC000-00600000 rw-p 001FC000 0000:0000 0 [stack (tid 8884)]
+00600000-006C7000 r--s 00000000 EE45:4341 281474976741117 /proc/cygdrive/c/Windows/System32/locale.nls
+...
+100400000-100401000 r--p 00000000 EE45:4341 281474978095037 /usr/bin/sh.exe
+100401000-100413000 r-xp 00001000 EE45:4341 281474978095037 /usr/bin/sh.exe
+100413000-100414000 rw-p 00013000 EE45:4341 281474978095037 /usr/bin/sh.exe
+...
+180010000-180020000 rw-s 00000000 0000:0000 0 [procinfo]
+180020000-180029000 rw-s 00000000 0000:0000 0 [cygwin-user-shared]
+180030000-18003C000 rw-s 00000000 0000:0000 0 [cygwin-shared]
+180040000-180041000 r--p 00000000 EE45:4341 2251799814294868 /usr/bin/cygwin1.dll
+180041000-18022D000 r-xp 00001000 EE45:4341 2251799814294868 /usr/bin/cygwin1.dll
+18022D000-180231000 rwxp 001ED000 EE45:4341 2251799814294868 /usr/bin/cygwin1.dll
+180231000-18026A000 rw-p 001F1000 EE45:4341 2251799814294868 /usr/bin/cygwin1.dll
+...
+800000000-800090000 rw-p 00000000 0000:0000 0 [heap]
+800090000-820000000 ===p 00090000 0000:0000 0 [heap]
+7FF4FDEB0000-7FF4FDEB5000 r--s 00000000 0000:0000 0
+7FF4FDEB5000-7FF4FDFB0000 ===s 00005000 0000:0000 0
+7FF4FDFB0000-7FF5FDFD0000 ===p 00000000 0000:0000 0
+...
+7FFBEEAC0000-7FFBEEAC1000 r--p 00000000 EE45:4341 844424934724994 /proc/cygdrive/c/Windows/System32/kernel32.dll
+7FFBEEAC1000-7FFBEEB36000 r-xp 00001000 EE45:4341 844424934724994 /proc/cygdrive/c/Windows/System32/kernel32.dll
+7FFBEEB36000-7FFBEEB68000 r--p 00076000 EE45:4341 844424934724994 /proc/cygdrive/c/Windows/System32/kernel32.dll
+7FFBEEB68000-7FFBEEB6A000 rw-p 000A8000 EE45:4341 844424934724994 /proc/cygdrive/c/Windows/System32/kernel32.dll
+7FFBEEB6A000-7FFBEEB72000 r--p 000AA000 EE45:4341 844424934724994 /proc/cygdrive/c/Windows/System32/kernel32.dll
+...
+</computeroutput>
+</screen>
+ </para>
+
+ <para>The <literal>address</literal> field is the address
+ space in the process that the mapping occupies.
+ The <literal>perms</literal> field is a set of permissions:
+
+ <variablelist termlength="4">
+ <varlistentry>
+ <term>r</term><listitem><para>read</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>w</term><listitem><para>write</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>x</term><listitem><para>execute</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>===</term><listitem><para>reserved</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>s</term><listitem><para>shared</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>g</term><listitem><para>guard</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>p</term><listitem><para>private</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ <para>The <literal>offset</literal> field is the offset
+ into the file/whatever;
+ <literal>dev</literal> is the device (major:minor);
+ <literal>inode</literal> is the inode on that device.
+ 0 indicates that no inode is associated with the memory
+ region, as would be the case with BSS (uninitialized data).
+ </para>
+
+ <para>The <literal>pathname</literal> field will usually
+ be the file that is backing the mapping.
+ </para>
+
+ <para>There are additional helpful pseudo-paths:
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term>[<literal>cygwin-shared</literal>]</term>
+ <listitem>
+ <para>Global shared Cygwin process information.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>cygwin-user-shared</literal>]</term>
+ <listitem>
+ <para>Global shared Cygwin user information.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>peb</literal>]</term>
+ <listitem>
+ <para>Windows Process Environment Block.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>procinfo</literal>]</term>
+ <listitem>
+ <para>Cygwin process information.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>shared-user-data</literal>]</term>
+ <listitem>
+ <para>Shared user information.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>heap</literal>]</term>
+ <listitem>
+ <para>The process's heap.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>stack</literal>]</term>
+ <listitem>
+ <para>
+ The initial process's (also known as the main
+ thread's) stack.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>stack</literal>
+ (tid <literal><tid></literal>)]
+ </term>
+ <listitem>
+ <para>
+ A thread's stack (where the
+ <literal><tid></literal> is a thread id).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>teb</literal>
+ (tid <literal><tid></literal>)]
+ </term>
+ <listitem>
+ <para>
+ Windows Thread Environment Block (where
+ <literal><tid></literal> is a thread id).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>[<literal>win heap <n>
+ default shared exec grow noserial debug</literal>]
+ </term>
+ <listitem>
+ <para>
+ Windows extended heap (where
+ <literal><n></literal> is a heap id)
+ and the rest of the words are heap flags:
+
+ <variablelist termlength="8" remap='TP'>
+ <varlistentry>
+ <term><literal>default</literal></term>
+ <listitem>
+ <para>default heap flags</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><literal>shared</literal></term>
+ <listitem>
+ <para>shareable and mapped heap flags</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><literal>exec</literal></term>
+ <listitem>
+ <para>executable heap flag</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><literal>grow</literal></term>
+ <listitem>
+ <para>growable heap flag</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><literal>noserial</literal></term>
+ <listitem>
+ <para>do not serialize heap flag</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><literal>debug</literal></term>
+ <listitem>
+ <para>debugged heap flag</para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ <para>If the <filename>pathname</filename> field is blank,
+ this is an anonymous mapping as obtained via
+ <citerefentry>
+ <refentrytitle>mmap</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>.
+ There is no easy way to coordinate this back to a process's
+ source, short of running it through
+ <citerefentry>
+ <refentrytitle>gdb</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>strace</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ or similar.
+ </para>
+
+ <para>
+ <filename>pathname</filename> is shown unescaped except
+ for newline characters, which are replaced with an
+ octal escape sequence.
+ As a result, it is not possible to determine whether the
+ original <filename>pathname</filename> contained a newline
+ character or the literal <literal>\e012</literal>
+ character sequence.
+ </para>
+
+ <para>
+ If the mapping is file-backed and the file has been deleted,
+ the string "<literal> (deleted)</literal>"
+ is appended to the <filename>pathname</filename>.
+ Note that this is ambiguous too.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/mountinfo</filename></term>
+ <listitem>
+ <para>
+ This file contains information about mount points in the
+ process's mount namespace (see
+ <citerefentry>
+ <refentrytitle>mount_namespaces</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>).
+ It supplies various information (e.g., propagation state, root
+ of mount for bind mounts, identifier for each mount and its
+ parent) that is missing from the (older)
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/mounts</filename>
+ file, and fixes various other problems with that file (e.g.,
+ nonextensibility, failure to distinguish per-mount versus
+ per-superblock options).
+ </para>
+
+ <para>The file contains lines of the form:</para>
+
+<screen>
+<computeroutput>
+36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue
+(1)(2)(3) (4) (5) (6) (?) (7) (8) (9) (10)
+</computeroutput>
+</screen>
+
+ <para>
+ The numbers in parentheses are labels for the descriptions below:
+
+ <variablelist termlength="4" remap='TP'>
+ <varlistentry>
+ <term>(1)</term>
+ <listitem>
+ <para>mount id: a unique id for the mount (may be reused after
+ <citerefentry>
+ <refentrytitle>umount</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(2)</term>
+ <listitem>
+ <para>parent id: the id of the parent mount (or of self for
+ the root of this mount namespace's mount tree).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(3)</term>
+ <listitem>
+ <para><emphasis remap="B">major</emphasis><literal>:</literal><emphasis remap="B">minor</emphasis>:
+ the value of <literal>st_dev</literal>
+ for files on this filesystem (see
+ <citerefentry>
+ <refentrytitle>stat</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(4)</term>
+ <listitem>
+ <para>root: the pathname of the directory in the filesystem
+ which forms the root of this mount.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(5)</term>
+ <listitem>
+ <para>mount point: the pathname of the mount point relative to
+ the process's root directory.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(6)</term>
+ <listitem>
+ <para>mount options: per-mount options (see
+ <citerefentry>
+ <refentrytitle>mount</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(?)</term>
+ <listitem>
+ <para>optional fields: zero or more fields of the form
+ "<emphasis>tag</emphasis><literal>[:</literal><emphasis>value</emphasis><literal>]</literal>";
+ see below.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(7)</term>
+ <listitem>
+ <para>separator: the end of the optional fields is marked by a
+ single hyphen.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(8)</term>
+ <listitem>
+ <para>filesystem type: the filesystem type in the form
+ "<emphasis>type</emphasis><literal>[.</literal><emphasis>subtype</emphasis><literal>]</literal>".
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(9)</term>
+ <listitem>
+ <para>mount source: filesystem-specific information or
+ "<literal>none</literal>".
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(10)</term>
+ <listitem>
+ <para>super options: per-superblock options (see
+ <citerefentry>
+ <refentrytitle>mount</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/mounts</filename></term>
+ <listitem>
+ <para>
+ This file lists all the filesystems currently mounted in the
+ process's mount namespace (see
+ <citerefentry>
+ <refentrytitle>mount_namespaces</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>).
+ The format of this file is documented in
+ <citerefentry>
+ <refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/pgid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the process group id for the
+ process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/ppid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the parent process id for the
+ process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/root</filename></term>
+ <listitem>
+ <para>
+ UNIX and Linux support the idea of a per-process root of the
+ filesystem, set by the
+ <citerefentry>
+ <refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry> system call.
+ This file is a symbolic link that points to the process's root
+ directory, and behaves in the same way as
+ <filename>exe</filename>, and
+ <filename>fd/*</filename>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/sid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the session id for the process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/stat</filename></term>
+ <listitem>
+ <para>
+ Status information about the process.
+ This is used by some implementations of
+ <citerefentry>
+ <refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>.
+ </para>
+
+ <para>
+ The fields, in order, with their proper
+ <citerefentry>
+ <refentrytitle>scanf</refentrytitle><manvolnum>3</manvolnum>
+ </citerefentry> format specifiers, are listed below.
+ </para>
+
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term>(1) <emphasis remap='I'>pid</emphasis> %d</term>
+ <listitem>
+ <para>The process id.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(2) <emphasis remap='I'>comm</emphasis> %s</term>
+ <listitem>
+ <para>
+ The filename of the executable, in parentheses.
+ This is visible whether or not the executable is swapped
+ out.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(3) <emphasis remap='I'>state</emphasis> %c</term>
+ <listitem>
+ <para>
+ One of the following characters, indicating process state:
+ </para>
+
+ <variablelist termlength="2">
+ <varlistentry>
+ <term>R</term>
+ <listitem>
+ <para>Runnable</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>O</term>
+ <listitem>
+ <para>Running</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>S</term>
+ <listitem>
+ <para>Sleeping in an interruptible wait</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>D</term>
+ <listitem>
+ <para>Waiting in uninterruptible disk sleep</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Z</term>
+ <listitem>
+ <para>Zombie</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>T</term>
+ <listitem>
+ <para>Stopped (on a signal) or trace stopped</para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(4) <emphasis remap='I'>ppid</emphasis> %d</term>
+ <listitem>
+ <para>The PID of the parent of this process.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(5) <emphasis remap='I'>pgrp</emphasis> %d</term>
+ <listitem>
+ <para>The process group id of the process.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(6) <emphasis remap='I'>session</emphasis> %d</term>
+ <listitem>
+ <para>The session id of the process.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(7) <emphasis remap='I'>tty_nr</emphasis> %d</term>
+ <listitem>
+ <para>
+ The controlling terminal of the process.
+ (The minor device number is contained in the combination
+ of bits 31 to 20 and 7 to 0; the major device number is in
+ bits 15 to 8.)
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(8) <emphasis remap='I'>tpgid</emphasis> %d</term>
+ <listitem>
+ <para>
+ The id of the foreground process group of the controlling
+ terminal of the process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(9) <emphasis remap='I'>flags</emphasis> %u</term>
+ <listitem>
+ <para>The kernel flags word of the process.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(10) <emphasis remap='I'>minflt</emphasis> %lu</term>
+ <listitem>
+ <para>
+ The number of minor faults the process has made which have
+ not required loading a memory page from disk.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(11) <emphasis remap='I'>cminflt</emphasis> %lu</term>
+ <listitem>
+ <para>
+ The number of minor faults that the process's waited-for
+ children have made.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(12) <emphasis remap='I'>majflt</emphasis> %lu</term>
+ <listitem>
+ <para>
+ The number of major faults the process has made which have
+ required loading a memory page from disk.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(13) <emphasis remap='I'>cmajflt</emphasis> %lu</term>
+ <listitem>
+ <para>
+ The number of major faults that the process's waited-for
+ children have made.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(14) <emphasis remap='I'>utime</emphasis> %lu</term>
+ <listitem>
+ <para>
+ Amount of time that this process has been scheduled in
+ user mode, measured in clock ticks (divide by
+ <literal>sysconf(_SC_CLK_TCK)</literal>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(15) <emphasis remap='I'>stime</emphasis> %lu</term>
+ <listitem>
+ <para>
+ Amount of time that this process has been scheduled in
+ kernel mode, measured in clock ticks (divide by
+ <literal>sysconf(_SC_CLK_TCK)</literal>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(16) <emphasis remap='I'>cutime</emphasis> %ld</term>
+ <listitem>
+ <para>
+ Amount of time that this process's waited-for children
+ have been scheduled in user mode, measured in clock ticks
+ (divide by <literal>sysconf(_SC_CLK_TCK)</literal>).
+ (See also
+ <citerefentry>
+ <refentrytitle>times</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(17) <emphasis remap='I'>cstime</emphasis> %ld</term>
+ <listitem>
+ <para>
+ Amount of time that this process's waited-for children
+ have been scheduled in kernel mode, measured in clock
+ ticks (divide by <literal>sysconf(_SC_CLK_TCK)</literal>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(18) <emphasis remap='I'>priority</emphasis> %ld</term>
+ <listitem>
+ <para>
+ For processes running a real-time scheduling policy
+ (<emphasis remap='I'>policy</emphasis> below; see
+ <citerefentry>
+ <refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>),
+ this is the negated scheduling priority, minus one; that
+ is, a number in the range -2 to -100, corresponding to
+ real-time priorities 1 to 99. For processes running
+ under a non-real-time scheduling policy, this is the raw
+ nice value
+ (<citerefentry>
+ <refentrytitle>setpriority</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>)
+ as represented in the kernel.
+ The kernel stores nice values as numbers in the range 0
+ (high) to 39 (low), corresponding to the user-visible nice
+ range of -20 to 19.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(19) <emphasis remap='I'>nice</emphasis> %ld</term>
+ <listitem>
+ <para>
+ The nice value (see
+ <citerefentry>
+ <refentrytitle>setpriority</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>), a value in the range 19 (low priority)
+ to -20 (high priority).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(20) <emphasis remap='I'>num_threads</emphasis> %ld</term>
+ <listitem>
+ <para>
+ Number of threads in this process. Currently shown as 0.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(21) <emphasis remap='I'>itrealvalue</emphasis> %ld</term>
+ <listitem>
+ <para>
+ The time in jiffies before the next
+ <literal>SIGALRM</literal>
+ is sent to the process due to an interval timer.
+ This field is no longer maintained, and is hard coded as 0.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(22) <emphasis remap='I'>starttime</emphasis> %llu</term>
+ <listitem>
+ <para>
+ The time the process started after system boot.
+ The value is expressed in clock ticks (divide by
+ <literal>sysconf(_SC_CLK_TCK)</literal>).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(23) <emphasis remap='I'>vsize</emphasis> %lu</term>
+ <listitem>
+ <para>Virtual memory size in bytes.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(24) <emphasis remap='I'>rss</emphasis> %ld</term>
+ <listitem>
+ <para>
+ Resident Set Size: number of pages the process has in real
+ memory.
+ This is just the pages which count toward text, data, or
+ stack space.
+ This does not include pages which have not been
+ demand-loaded in, or which are swapped out.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(25) <emphasis remap='I'>rsslim</emphasis> %lu</term>
+ <listitem>
+ <para>
+ Current soft limit in bytes on the rss of the process; see
+ the description of <literal>RLIMIT_RSS</literal> in
+ <citerefentry>
+ <refentrytitle>getrlimit</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/statm</filename></term>
+ <listitem>
+ <para>
+ Provides information about memory usage, measured in pages.
+ The columns are:
+
+ <variablelist termlength="12">
+ <varlistentry>
+ <term>(1) size</term>
+ <listitem>
+ <para>total program size
+ (same as VmSize in <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/status</filename>)</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(2) resident</term>
+ <listitem>
+ <para>resident set size
+ (same as VmRSS in <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/status</filename>)</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(3) shared</term>
+ <listitem>
+ <para>number of resident shared pages
+ (i.e., backed by a file) (same as RssFile+RssShmem in
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/status</filename>)</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(4) text</term>
+ <listitem><para>text (code)</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(5) lib</term>
+ <listitem><para>library</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(6) data</term>
+ <listitem><para>data + stack</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(7) dt</term>
+ <listitem><para>dirty pages (always 0)</para></listitem>
+ </varlistentry>
+ </variablelist>
+
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/status</filename></term>
+ <listitem>
+ <para>
+ Provides much of the information in
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/stat</filename> and
+ <filename>/proc/<emphasis remap='I'>[pid]</emphasis>/statm</filename>
+ in a format that's easier for humans to parse.
+ Here's an example:
+
+ <screen>
+ <prompt>$</prompt> <userinput>cat /proc/$$/status</userinput>
+ <computeroutput>
+ Name: bash
+ Umask: 0022
+ State: S (sleeping)
+ Tgid: 17248
+ Pid: 17248
+ PPid: 17200
+ Uid: 1000 1000 1000 1000
+ Gid: 100 100 100 100
+ VmSize: 131168 kB
+ VmLck: 0 kB
+ VmRSS: 13484 kB
+ VmData: 10332 kB
+ VmStk: 136 kB
+ VmExe: 992 kB
+ VmLib: 2104 kB
+ SigPnd: 0000000000000000
+ SigBlk: 0000000000010000
+ SigIgn: 0000000000384004
+ </computeroutput>
+ </screen>
+
+ </para>
+
+ <para>The fields are as follows:
+ <itemizedlist remap='IP+bullet'>
+ <listitem>
+ <para>
+ <emphasis remap='I'>Name</emphasis>:
+ Command run by this process.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>Umask</emphasis>:
+ Process umask, expressed in octal with a leading zero; see
+ <citerefentry>
+ <refentrytitle>umask</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>State</emphasis>:
+ Current state of the process.
+ One of:
+
+ <variablelist termlength="2" remap='TP'>
+ <varlistentry>
+ <term>R</term>
+ <listitem><para>runnable</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>O</term>
+ <listitem><para>running</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>S</term>
+ <listitem><para>sleeping</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>D</term>
+ <listitem><para>disk sleep</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>T</term>
+ <listitem><para>stopped or tracing stop</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term>Z</term>
+ <listitem><para>zombie</para></listitem>
+
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>Tgid</emphasis>:
+ Thread group id (i.e., Process id).
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>Pid</emphasis>:
+ Thread id (see
+ <citerefentry>
+ <refentrytitle>gettid</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>PPid</emphasis>:
+ PID of parent process.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>Uid</emphasis>,
+ <emphasis remap='I'>Gid</emphasis>:
+ Real, effective, saved set, and filesystem UIDs (GIDs).
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>VmSize</emphasis>:
+ Virtual memory size.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>VmLck</emphasis>:
+ Locked memory size (see
+ <citerefentry>
+ <refentrytitle>mlock</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>VmRSS</emphasis>:
+ Resident set size.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>VmData</emphasis>,
+ <emphasis remap='I'>VmStk</emphasis>,
+ <emphasis remap='I'>VmExe</emphasis>:
+ Size of data, stack, and text segments.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>VmLib</emphasis>:
+ Shared library code size.
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>SigPnd</emphasis>:
+ Number of signals pending for process as a whole (see
+ <citerefentry>
+ <refentrytitle>pthreads</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry> and
+ <citerefentry>
+ <refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum></citerefentry>).
+ </para>
+
+ </listitem>
+ <listitem>
+ <para>
+ <emphasis remap='I'>SigBlk</emphasis>,
+ <emphasis remap='I'>SigIgn</emphasis>:
+ Masks indicating signals being blocked and ignored (see
+ <citerefentry>
+ <refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>).
+ </para>
+
+ </listitem>
+ </itemizedlist>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/uid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the user id for the process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/winexename</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the Windows pathname of the
+ executed command.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/<emphasis remap='I'>[pid]</emphasis>/winpid</filename></term>
+ <listitem>
+ <para>
+ This read-only file contains the Windows process id for the
+ process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/cpuinfo</filename></term>
+ <listitem>
+ <para>
+ This is a collection of CPU and system architecture dependent
+ items, for each supported architecture a different list.
+ Two common entries are <emphasis remap='I'>processor</emphasis>
+ which gives CPU number and
+ <emphasis remap='I'>bogomips</emphasis>, a system constant
+ that is calculated during kernel initialization.
+ SMP machines have information for each CPU.
+ The
+ <citerefentry>
+ <refentrytitle>lscpu</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>
+ command gathers its information from this file.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/cygdrive</filename></term>
+ <listitem>
+ <para>
+ This file is a symbolic link that points to the user's
+ Windows mapped drive mount point, similar to
+ <emphasis remap='I'>root</emphasis>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/devices</filename></term>
+ <listitem>
+ <para>
+ Text listing of major numbers and device groups.
+ This can be used by <command>makedev</command>
+ scripts for consistency with the system.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/filesystems</filename></term>
+ <listitem>
+ <para>
+ A text listing of the filesystems which are supported by Cygwin.
+ (See also
+ <citerefentry>
+ <refentrytitle>filesystems</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>.)
+ If a filesystem is marked with "nodev", this means that it
+ does not require a block device to be mounted (e.g., virtual
+ filesystem, network filesystem).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/loadavg</filename></term>
+ <listitem>
+ <para>
+ The first three fields in this file are load average figures
+ giving the number of jobs in the run queue (state R)
+ averaged over 1, 5, and 15 minutes.
+ They are the same as the load average numbers given by
+ <citerefentry>
+ <refentrytitle>uptime</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry> and other programs.
+ The fourth field consists of two numbers separated by a slash (/).
+ The first of these is the number of currently runnable
+ scheduling entities (processes, threads).
+ The value after the slash is the number of scheduling entities
+ that currently exist on the system.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/meminfo</filename></term>
+ <listitem>
+ <para>
+ This file reports statistics about memory usage on the system.
+ It is used by
+ <citerefentry>
+ <refentrytitle>free</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>
+ to report the amount of free and used memory (both physical
+ and swap) on the system as well as the shared memory and
+ buffers used by the system.
+ Each line of the file consists of a parameter name, followed by
+ a colon, the value of the parameter, and an option unit of
+ measurement (e.g., "kB").
+ The list below describes the parameter names and the format
+ specifier required to read the field value.
+ Some fields are displayed only if the system was configured
+ with various options; those dependencies are noted in the
+ list.
+ </para>
+
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term><emphasis remap='I'>MemTotal</emphasis> %lu</term>
+ <listitem>
+ <para>
+ Total usable RAM (i.e., physical RAM minus a few reserved
+ bits and the system binary code).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>MemFree</emphasis> %lu</term>
+ <listitem>
+ <para>
+ The sum of <emphasis remap='I'>LowFree</emphasis> +
+ <emphasis remap='I'>HighFree</emphasis>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>HighTotal</emphasis> %lu</term>
+ <listitem>
+ <para>Total amount of highmem.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>HighFree</emphasis> %lu</term>
+ <listitem>
+ <para>Amount of free highmem.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>LowTotal</emphasis> %lu</term>
+ <listitem>
+ <para>
+ Total amount of lowmem.
+ Lowmem is memory which can be used for everything that
+ highmem can be used for, but it is also available for the
+ system's use for its own data structures.
+ Bad things happen when you're out of lowmem.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>LowFree</emphasis> %lu</term>
+ <listitem>
+ <para>Amount of free lowmem.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>SwapTotal</emphasis> %lu</term>
+ <listitem>
+ <para>Total amount of swap space available.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>SwapFree</emphasis> %lu</term>
+ <listitem>
+ <para>Amount of swap space that is currently unused.</para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/misc</filename></term>
+ <listitem>
+ <para>
+ Text listing of minor device numbers and names of devices with
+ major device number of the <literal>misc</literal> device group.
+ This can be used by <command>makedev</command> scripts
+ for consistency with the system.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/mounts</filename></term>
+ <listitem>
+ <para>
+ With the introduction of per-process mount namespaces, this file
+ became a link to
+ <filename>/proc/self/mounts</filename>,
+ which lists the mount points of the process's own mount
+ namespace.
+ The format of this file is documented in
+ <citerefentry>
+ <refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum>
+ </citerefentry>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/net</filename></term>
+ <listitem>
+ <para>
+ This directory contains various files and subdirectories
+ containing information about the networking layer.
+ The files contain ASCII structures and are, therefore, readable
+ with
+ <citerefentry>
+ <refentrytitle>cat</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>.
+ However, the standard
+ <citerefentry>
+ <refentrytitle>netstat</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>
+ suite provides much cleaner access to these files.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/net/if_inet6</filename></term>
+ <listitem>
+ <para>
+ This file contains information about IP V6 interface adapters,
+ if used.
+ Each line represents an IP V6 interface adapter.
+ </para>
+
+<screen>
+<computeroutput>
+fe800000000000002c393d3da6108636 12 40 20 80 {C6B5FBE5-A3AC-4DB0-A308-8EE94E1406A4}
+fe8000000000000039da016f76bd92bc 13 40 20 20 {E06B8972-0918-41FC-851B-090C446C7D1C}
+fe8000000000000050ba9cedf1fe1628 0b 40 20 20 {680ED6FD-DFAC-4398-AA85-FB33E17E38EA}
+fe8000000000000030c5c6a0b30f109d 11 40 20 20 {B9E39F53-1659-4065-BDA5-F41162250E03}
+20021840ac2c12343427e3b9ec6fa585 08 40 00 80 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c12342403e3b2c7a5a32f 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c1234284e8d0ecb4160cb 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c123468cb06ea72f1d678 08 80 00 80 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c12346cb59aca97c36e3b 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c123498af9881de1fb828 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c1234cd62a3d73a498611 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+20021840ac2c1234e410c873be09df93 08 80 00 20 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+fe800000000000003427e3b9ec6fa585 08 40 20 80 {4083A7F8-99CF-4220-8715-6FDF268B002F}
+00000000000000000000000000000001 01 80 10 80 {2B5345AC-7502-11EA-AC73-806E6F6E6963}
+ (1) (2)(3)(4)(5) (6)
+</computeroutput>
+</screen>
+
+ <para>The fields in each line are:
+
+ <variablelist termlength="4" remap='TP'>
+ <varlistentry>
+ <term>(1)</term>
+ <listitem>
+ <para>The IP V6 address of the interface adapter.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(2)</term>
+ <listitem>
+ <para>The IP V6 interface adapter index.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(3)</term>
+ <listitem>
+ <para>
+ The prefix length of the IP V6 interface address.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(4)</term>
+ <listitem>
+ <para>The scope of the IP V6 interface address.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(5)</term>
+ <listitem>
+ <para>The state of the IP V6 interface address.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(6)</term>
+ <listitem>
+ <para>
+ The DUID/GUID/UUID of the IP V6 interface adapter.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ <para>
+ The last number exists only for compatibility reasons and is
+ always 1.
+ </para>
+
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/partitions</filename></term>
+ <listitem>
+ <para>
+ Contains the major and minor numbers of each partition as well
+ as the number of 1024-byte blocks and the partition name.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/registry</filename></term>
+ <listitem>
+ <para>
+ Under Cygwin, this directory contains subdirectories for
+ registry paths, keys, and subkeys, and files named for registry
+ values which contain registry data, for the current process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/registry32</filename></term>
+ <listitem>
+ <para>
+ Under 64 bit Windows, this directory contains subdirectories for
+ registry paths, keys, and subkeys, and files named for registry
+ values which contain registry data, for 32 bit processes.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/registry64</filename></term>
+ <listitem>
+ <para>
+ Under 64 bit Windows, this directory contains subdirectories for
+ registry paths, keys, and subkeys, and files named for registry
+ values which contain registry data, for 64 bit processes.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/self</filename></term>
+ <listitem>
+ <para>
+ This directory refers to the process accessing the
+ <filename>/proc</filename> filesystem, and is identical to the
+ <filename>/proc</filename> directory named by the process id
+ of the same process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/stat</filename></term>
+ <listitem>
+ <para>
+ system statistics.
+ Varies with architecture.
+ Common entries include:
+ <variablelist remap='TP'>
+ <varlistentry>
+ <term><emphasis remap='I'>cpu 10132153 0 3084719 46828483</emphasis></term>
+ <listitem>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>cpu0 1393280 0 572056 13343292</emphasis></term>
+ <listitem>
+ <para>
+ The amount of time, measured in units of USER_HZ
+ (1/100ths of a second on most architectures, use
+ <literal>sysconf(_SC_CLK_TCK)</literal>
+ to obtain the right value), that the system ("cpu"
+ line) or the specific CPU
+ ("cpu <emphasis remap='I'>N</emphasis>" line)
+ spent in various states:
+
+ <variablelist termlength="10" remap='TP'>
+ <varlistentry>
+ <term>(1) <emphasis remap='I'>user</emphasis></term>
+ <listitem>
+ <para>Time spent in user mode.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(2) <emphasis remap='I'>nice</emphasis></term>
+ <listitem>
+ <para>
+ Time spent in user mode with low priority
+ (nice).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(3) <emphasis remap='I'>system</emphasis></term>
+ <listitem>
+ <para>Time spent in system mode.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>(4) <emphasis remap='I'>idle</emphasis></term>
+ <listitem>
+ <para>Time spent in the idle task.</para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>page 5741 1808</emphasis></term>
+ <listitem>
+ <para>
+ The number of pages the system paged in and the number
+ that were paged out (from disk).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>swap 1 0</emphasis></term>
+ <listitem>
+ <para>
+ The number of swap pages that have been brought in and
+ out.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>intr 1462898</emphasis></term>
+ <listitem>
+ <para>The number of interrupts serviced.</para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>ctxt 115315</emphasis></term>
+ <listitem>
+ <para>
+ The number of context switches that the system
+ underwent.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><emphasis remap='I'>btime 769041601</emphasis></term>
+ <listitem>
+ <para>
+ boot time, in seconds since the Epoch,
+ 1970-01-01 00:00:00 +0000 (UTC).
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/swaps</filename></term>
+ <listitem>
+ <para>
+ Swap areas in use.
+ See also
+ <citerefentry>
+ <refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/sys</filename></term>
+ <listitem>
+ <para>
+ This directory contains a number of files and subdirectories
+ linking to Windows objects, which can be read using these
+ entries.
+ </para>
+
+ <para>
+ String values may be terminated by either '\0'
+ or '\n'.
+ </para>
+
+ <para>
+ Integer and long values may be either in decimal or in
+ hexadecimal notation (e.g. 0x3FFF).
+ Multiple integer or long values may be separated by any of the
+ following whitespace characters:
+ ' ', '\t', or
+ '\n'.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/sysvipc</filename></term>
+ <listitem>
+ <para>
+ Subdirectory containing the pseudo-files
+ <filename>msg</filename>, <filename>sem</filename>and
+ <filename>shm</filename>.
+ These files list the System V Interprocess Communication (IPC)
+ objects (respectively: message queues, semaphores, and shared
+ memory) that currently exist on the system, providing similar
+ information to that available via
+ <citerefentry>
+ <refentrytitle>ipcs</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>.
+ These files are only available if the cygserver Cygwin service
+ is running.
+ These files have headers and are formatted (one IPC object per
+ line) for easy understanding.
+ <citerefentry>
+ <refentrytitle>svipc</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>
+ provides further background on the information shown by these
+ files.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/uptime</filename></term>
+ <listitem>
+ <para>
+ This file contains two numbers (values in seconds): the uptime
+ of the system (including time spent in suspend) and the amount
+ of time spent in the idle process.
+ </para>
+
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><filename>/proc/version</filename></term>
+ <listitem>
+ <para>
+ This string identifies the Cygwin version that is currently
+ running.
+ For example:
+
+<screen>
+<computeroutput>
+CYGWIN_NT-10.0-18363 version 3.1.7-340.x86_64 (corinna@calimero) (gcc version 9.3.0 20200312 (Fedora Cygwin 9.3.0-1) (GCC) ) 2020-08-22 17:48 UTC
+</computeroutput>
+</screen>
+
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
+ </refsect1>
+
+ <refsect1 id='proc-notes'><title>Notes</title>
+ <para>
+ Many files contain strings (e.g., the environment and command
+ line) that are in the internal format, with subfields terminated
+ by null bytes ('\0').
+ When inspecting such files, you may find that the results are
+ more readable if you use a command of the following form to
+ display them:
+
+ <screen>
+ <prompt>$</prompt> <userinput>cat -A <emphasis remap='I'>file</emphasis></userinput>
+ </screen>
+ </para>
+
+ <para>
+ This manual page is incomplete, possibly inaccurate, and is the kind
+ of thing that needs to be updated very often.
+ </para>
+ </refsect1>
+
+ <refsect1 id='proc-see_also'><title>See Also</title>
+ <para>
+ <citerefentry>
+ <refentrytitle>cat</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>find</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>free</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>pstree</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>tr</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>uptime</refentrytitle><manvolnum>1</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>mmap</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>readlink</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>syslog</refentrytitle><manvolnum>2</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>hier</refentrytitle><manvolnum>7</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>arp</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>netstat</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>,
+ <citerefentry>
+ <refentrytitle>route</refentrytitle><manvolnum>8</manvolnum>
+ </citerefentry>.
+ </para>
+ </refsect1>
+ </refentry>
</sect2>
<sect2 id="pathnames-proc-registry"><title>The /proc/registry filesystem</title>