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<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>proc</title><link rel="stylesheet" type="text/css" href="docbook.css"><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot"><link rel="home" href="cygwin-ug-net.html" title="Cygwin User's Guide"><link rel="up" href="using-specialnames.html#pathnames-proc" title="The /proc filesystem"><link rel="prev" href="using-specialnames.html" title="Special filenames"><link rel="next" href="using-cygwinenv.html" title="The CYGWIN environment variable"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">proc</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="using-specialnames.html">Prev</a> </td><th width="60%" align="center">The /proc filesystem</th><td width="20%" align="right"> <a accesskey="n" href="using-cygwinenv.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="proc"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>proc — process and system information pseudo-filesystem</p></div><div class="refsect1"><a name="proc-desc"></a><h2>Description</h2><p>The <code class="filename">proc</code> filesystem is a pseudo-filesystem
which provides an interface to Cygwin data structures.
It is commonly mounted at <code class="filename">/proc</code>.
Typically, it is mounted automatically by the system.
</p><div class="refsect2"><a name="proc-overview"></a><h3>Overview</h3><p>Underneath <code class="filename">/proc</code>, there are the following
general groups of files and subdirectories:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code> subdirectories</span></dt><dd><p>Each one of these subdirectories contains files and
subdirectories exposing information about the process with the
corresponding process id.
</p><p>The <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code> subdirectories are
visible when iterating through <code class="filename">/proc</code> with
<span class="citerefentry"><span class="refentrytitle">readdir</span>(2)</span>
(and thus are visible when one uses
<span class="citerefentry"><span class="refentrytitle">ls</span>(1)</span>
to view the contents of <code class="filename">/proc</code>).
</p></dd><dt><span class="term"><code class="filename">/proc/self</code></span></dt><dd><p>When a process accesses this magic symbolic link, it resolves
to the process's own <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code> directory.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[a-z]*</em></span></code></span></dt><dd><p>Various other files and subdirectories under
<code class="filename">/proc</code> expose system-wide information.
</p></dd></dl></div><p>All of the above are described in more detail below.
</p></div><div class="refsect2"><a name="proc-files-and-directories"></a><h3>Files and directories</h3><p>
The following list provides details of many of the files
and directories under the <code class="filename">/proc</code> hierarchy.
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code></span></dt><dd><p>
There is a numerical subdirectory for each running
process; the subdirectory is named by the process id.
Each <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code> subdirectory
contains the pseudo-files and directories described below.
</p><p>The files inside each <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span></code>
directory are normally owned by the effective user and
effective group id of the process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/cmdline</code></span></dt><dd><p>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').
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/ctty</code></span></dt><dd><p>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/cwd</code></span></dt><dd><p>
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:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>cd /proc/20/cwd; /bin/pwd</code></strong>
</pre><p>
</p><p>Note that the <span class="emphasis"><em>pwd</em></span> command
is often a shell built-in, and might not work properly. In
<span class="citerefentry"><span class="refentrytitle">bash</span>(1)</span>,
you may use <strong class="userinput"><code>pwd -P</code></strong>.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/environ</code></span></dt><dd><p>
This read-only file contains the current environment that may
have been changed by the currently executing program.
The entries are separated by null bytes ('\0'),
and there may be a null byte at the end.
Thus, to print out the environment of process 1, you would do:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>cat -A /proc/1/environ</code></strong>
</pre><p>
</p><p>If, after an
<span class="citerefentry"><span class="refentrytitle">execve</span>(2)</span>,
the process modifies its environment (e.g., by calling
functions such as
<span class="citerefentry"><span class="refentrytitle">putenv</span>(3)</span>
or modifying the
<span class="citerefentry"><span class="refentrytitle">environ</span>(7)</span>
variable directly), this file will reflect those changes.
That may not be the case on other systems such as Linux.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/exe</code></span></dt><dd><p>
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 <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/exe</code>
to run another copy of the same executable that is being run by
process <span class="emphasis"><em>[pid]</em></span>.
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/exe</code> is a pointer to
the binary which was executed, and appears as a symbolic link.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/exename</code></span></dt><dd><p>
This read-only file contains the actual pathname of the executed
command.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/fd/</code></span></dt><dd><p>
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.
</p><p>
For file descriptors for pipes and sockets, the entries will
be symbolic links whose content is the file type with the
inode. A
<span class="citerefentry"><span class="refentrytitle">readlink</span>(2)</span>
call on this file returns a string in the format:
<code class="literal">type:<span class="emphasis"><em>[inode]</em></span></code>
</p><p>For example, <code class="literal">socket:[2248868]</code>
will be a socket and its inode is 2248868.
</p><p>
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
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/fd</code> files as command-line
arguments.
For example, assuming that <code class="option">-i</code> is the flag
designating an input file and <code class="option">-o</code> is the flag
designating an output file:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>foobar -i /proc/self/fd/0 -o /proc/self/fd/1 ...</code></strong>
</pre><p>
and you have a working filter.
</p><p><code class="filename">/proc/self/fd/N</code> is approximately
the same as <code class="filename">/dev/fd/N</code> in some Unix
and Unix-like systems.
Most Linux <span class="command"><strong>makedev</strong></span> scripts symbolically
link <code class="filename">/dev/fd</code> to
<code class="filename">/proc/self/fd</code>, in fact.
</p><p>Most systems provide symbolic links
<code class="filename">/dev/stdin</code>,
<code class="filename">/dev/stdout</code>, and
<code class="filename">/dev/stderr</code>, which respectively link
to the files <code class="literal">0</code>, <code class="literal">1</code>,
and <code class="literal">2</code> in <code class="filename">/proc/self/fd</code>.
Thus the example command above could be written as:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>foobar -i /dev/stdin -o /dev/stdout ...</code></strong>
</pre><p>
</p><p>
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
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/fd</code> 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:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>echo test | sudo -u nobody cat</code></strong>
<code class="computeroutput">test</code>
<code class="prompt">$</code> <strong class="userinput"><code>echo test | sudo -u nobody cat /proc/self/fd/0</code></strong>
<code class="computeroutput">cat: /proc/self/fd/0: Permission denied</code>
</pre><p>
</p><p>
File descriptor 0 refers to the pipe created by the shell and
owned by that shell's user, which is not
<code class="literal">nobody</code>, so <span class="command"><strong>cat</strong></span>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/gid</code></span></dt><dd><p>
This read-only file contains the primary group id for the
process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/maps</code></span></dt><dd><p>
A file containing the currently mapped memory regions and their
access permissions. See
<span class="citerefentry"><span class="refentrytitle">mmap</span>(2)</span>
for some further information about memory mappings.
</p><p>The format of the file is:
</p><pre class="screen">
<span class="emphasis"><em>address perms offset dev inode pathname</em></span>
<code class="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
...
</code>
</pre><p>
</p><p>The <code class="literal">address</code> field is the address
space in the process that the mapping occupies.
The <code class="literal">perms</code> field is a set of permissions:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">r</span></dt><dd><p>read</p></dd><dt><span class="term">w</span></dt><dd><p>write</p></dd><dt><span class="term">x</span></dt><dd><p>execute</p></dd><dt><span class="term">===</span></dt><dd><p>reserved</p></dd><dt><span class="term">s</span></dt><dd><p>shared</p></dd><dt><span class="term">g</span></dt><dd><p>guard</p></dd><dt><span class="term">p</span></dt><dd><p>private</p></dd></dl></div><p>
</p><p>The <code class="literal">offset</code> field is the offset
into the file/whatever;
<code class="literal">dev</code> is the device (major:minor);
<code class="literal">inode</code> 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).
</p><p>The <code class="literal">pathname</code> field will usually
be the file that is backing the mapping.
</p><p>There are additional helpful pseudo-paths:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">[<code class="literal">cygwin-shared</code>]</span></dt><dd><p>Global shared Cygwin process information.</p></dd><dt><span class="term">[<code class="literal">cygwin-user-shared</code>]</span></dt><dd><p>Global shared Cygwin user information.</p></dd><dt><span class="term">[<code class="literal">peb</code>]</span></dt><dd><p>Windows Process Environment Block.</p></dd><dt><span class="term">[<code class="literal">procinfo</code>]</span></dt><dd><p>Cygwin process information.</p></dd><dt><span class="term">[<code class="literal">shared-user-data</code>]</span></dt><dd><p>Shared user information.</p></dd><dt><span class="term">[<code class="literal">heap</code>]</span></dt><dd><p>The process's heap.</p></dd><dt><span class="term">[<code class="literal">stack</code>]</span></dt><dd><p>
The initial process's (also known as the main
thread's) stack.
</p></dd><dt><span class="term">[<code class="literal">stack</code>
(tid <code class="literal"><tid></code>)]
</span></dt><dd><p>
A thread's stack (where the
<code class="literal"><tid></code> is a thread id).
</p></dd><dt><span class="term">[<code class="literal">teb</code>
(tid <code class="literal"><tid></code>)]
</span></dt><dd><p>
Windows Thread Environment Block (where
<code class="literal"><tid></code> is a thread id).
</p></dd><dt><span class="term">[<code class="literal">win heap <n>
default shared exec grow noserial debug</code>]
</span></dt><dd><p>
Windows extended heap (where
<code class="literal"><n></code> is a heap id)
and the rest of the words are heap flags:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">default</code></span></dt><dd><p>default heap flags</p></dd><dt><span class="term"><code class="literal">shared</code></span></dt><dd><p>shareable and mapped heap flags</p></dd><dt><span class="term"><code class="literal">exec</code></span></dt><dd><p>executable heap flag</p></dd><dt><span class="term"><code class="literal">grow</code></span></dt><dd><p>growable heap flag</p></dd><dt><span class="term"><code class="literal">noserial</code></span></dt><dd><p>do not serialize heap flag</p></dd><dt><span class="term"><code class="literal">debug</code></span></dt><dd><p>debugged heap flag</p></dd></dl></div><p>
</p></dd></dl></div><p>
</p><p>If the <code class="filename">pathname</code> field is blank,
this is an anonymous mapping as obtained via
<span class="citerefentry"><span class="refentrytitle">mmap</span>(2)</span>.
There is no easy way to coordinate this back to a process's
source, short of running it through
<span class="citerefentry"><span class="refentrytitle">gdb</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">strace</span>(1)</span>,
or similar.
</p><p>
<code class="filename">pathname</code> 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 <code class="filename">pathname</code> contained a newline
character or the literal <code class="literal">\e012</code>
character sequence.
</p><p>
If the mapping is file-backed and the file has been deleted,
the string "<code class="literal"> (deleted)</code>"
is appended to the <code class="filename">pathname</code>.
Note that this is ambiguous too.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/mountinfo</code></span></dt><dd><p>
This file contains information about mount points in the
process's mount namespace (see
<span class="citerefentry"><span class="refentrytitle">mount_namespaces</span>(7)</span>).
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)
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/mounts</code>
file, and fixes various other problems with that file (e.g.,
nonextensibility, failure to distinguish per-mount versus
per-superblock options).
</p><p>The file contains lines of the form:</p><pre class="screen">
<code class="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)
</code>
</pre><p>
The numbers in parentheses are labels for the descriptions below:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">(1)</span></dt><dd><p>mount id: a unique id for the mount (may be reused after
<span class="citerefentry"><span class="refentrytitle">umount</span>(2)</span>).
</p></dd><dt><span class="term">(2)</span></dt><dd><p>parent id: the id of the parent mount (or of self for
the root of this mount namespace's mount tree).
</p></dd><dt><span class="term">(3)</span></dt><dd><p><span class="emphasis"><em>major</em></span><code class="literal">:</code><span class="emphasis"><em>minor</em></span>:
the value of <code class="literal">st_dev</code>
for files on this filesystem (see
<span class="citerefentry"><span class="refentrytitle">stat</span>(2)</span>).
</p></dd><dt><span class="term">(4)</span></dt><dd><p>root: the pathname of the directory in the filesystem
which forms the root of this mount.
</p></dd><dt><span class="term">(5)</span></dt><dd><p>mount point: the pathname of the mount point relative to
the process's root directory.
</p></dd><dt><span class="term">(6)</span></dt><dd><p>mount options: per-mount options (see
<span class="citerefentry"><span class="refentrytitle">mount</span>(2)</span>).
</p></dd><dt><span class="term">(?)</span></dt><dd><p>optional fields: zero or more fields of the form
"<span class="emphasis"><em>tag</em></span><code class="literal">[:</code><span class="emphasis"><em>value</em></span><code class="literal">]</code>";
see below.
</p></dd><dt><span class="term">(7)</span></dt><dd><p>separator: the end of the optional fields is marked by a
single hyphen.
</p></dd><dt><span class="term">(8)</span></dt><dd><p>filesystem type: the filesystem type in the form
"<span class="emphasis"><em>type</em></span><code class="literal">[.</code><span class="emphasis"><em>subtype</em></span><code class="literal">]</code>".
</p></dd><dt><span class="term">(9)</span></dt><dd><p>mount source: filesystem-specific information or
"<code class="literal">none</code>".
</p></dd><dt><span class="term">(10)</span></dt><dd><p>super options: per-superblock options (see
<span class="citerefentry"><span class="refentrytitle">mount</span>(2)</span>).
</p></dd></dl></div><p>
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/mounts</code></span></dt><dd><p>
This file lists all the filesystems currently mounted in the
process's mount namespace (see
<span class="citerefentry"><span class="refentrytitle">mount_namespaces</span>(7)</span>).
The format of this file is documented in
<span class="citerefentry"><span class="refentrytitle">fstab</span>(5)</span>.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/pgid</code></span></dt><dd><p>
This read-only file contains the process group id for the
process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/ppid</code></span></dt><dd><p>
This read-only file contains the parent process id for the
process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/root</code></span></dt><dd><p>
UNIX and Linux support the idea of a per-process root of the
filesystem, set by the
<span class="citerefentry"><span class="refentrytitle">chroot</span>(2)</span> system call.
This file is a symbolic link that points to the process's root
directory, and behaves in the same way as
<code class="filename">exe</code>, and
<code class="filename">fd/*</code>.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/sid</code></span></dt><dd><p>
This read-only file contains the session id for the process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/stat</code></span></dt><dd><p>
Status information about the process.
This is used by some implementations of
<span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span>.
</p><p>
The fields, in order, with their proper
<span class="citerefentry"><span class="refentrytitle">scanf</span>(3)</span> format specifiers, are listed below.
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">(1) <span class="emphasis"><em>pid</em></span> %d</span></dt><dd><p>The process id.</p></dd><dt><span class="term">(2) <span class="emphasis"><em>comm</em></span> %s</span></dt><dd><p>
The filename of the executable, in parentheses.
This is visible whether or not the executable is swapped
out.
</p></dd><dt><span class="term">(3) <span class="emphasis"><em>state</em></span> %c</span></dt><dd><p>
One of the following characters, indicating process state:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">R</span></dt><dd><p>Runnable</p></dd><dt><span class="term">O</span></dt><dd><p>Running</p></dd><dt><span class="term">S</span></dt><dd><p>Sleeping in an interruptible wait</p></dd><dt><span class="term">D</span></dt><dd><p>Waiting in uninterruptible disk sleep</p></dd><dt><span class="term">Z</span></dt><dd><p>Zombie</p></dd><dt><span class="term">T</span></dt><dd><p>Stopped (on a signal) or trace stopped</p></dd></dl></div></dd><dt><span class="term">(4) <span class="emphasis"><em>ppid</em></span> %d</span></dt><dd><p>The PID of the parent of this process.</p></dd><dt><span class="term">(5) <span class="emphasis"><em>pgrp</em></span> %d</span></dt><dd><p>The process group id of the process.</p></dd><dt><span class="term">(6) <span class="emphasis"><em>session</em></span> %d</span></dt><dd><p>The session id of the process.</p></dd><dt><span class="term">(7) <span class="emphasis"><em>tty_nr</em></span> %d</span></dt><dd><p>
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.)
</p></dd><dt><span class="term">(8) <span class="emphasis"><em>tpgid</em></span> %d</span></dt><dd><p>
The id of the foreground process group of the controlling
terminal of the process.
</p></dd><dt><span class="term">(9) <span class="emphasis"><em>flags</em></span> %u</span></dt><dd><p>The kernel flags word of the process.</p></dd><dt><span class="term">(10) <span class="emphasis"><em>minflt</em></span> %lu</span></dt><dd><p>
The number of minor faults the process has made which have
not required loading a memory page from disk.
</p></dd><dt><span class="term">(11) <span class="emphasis"><em>cminflt</em></span> %lu</span></dt><dd><p>
The number of minor faults that the process's waited-for
children have made.
</p></dd><dt><span class="term">(12) <span class="emphasis"><em>majflt</em></span> %lu</span></dt><dd><p>
The number of major faults the process has made which have
required loading a memory page from disk.
</p></dd><dt><span class="term">(13) <span class="emphasis"><em>cmajflt</em></span> %lu</span></dt><dd><p>
The number of major faults that the process's waited-for
children have made.
</p></dd><dt><span class="term">(14) <span class="emphasis"><em>utime</em></span> %lu</span></dt><dd><p>
Amount of time that this process has been scheduled in
user mode, measured in clock ticks (divide by
<code class="literal">sysconf(_SC_CLK_TCK)</code>).
</p></dd><dt><span class="term">(15) <span class="emphasis"><em>stime</em></span> %lu</span></dt><dd><p>
Amount of time that this process has been scheduled in
kernel mode, measured in clock ticks (divide by
<code class="literal">sysconf(_SC_CLK_TCK)</code>).
</p></dd><dt><span class="term">(16) <span class="emphasis"><em>cutime</em></span> %ld</span></dt><dd><p>
Amount of time that this process's waited-for children
have been scheduled in user mode, measured in clock ticks
(divide by <code class="literal">sysconf(_SC_CLK_TCK)</code>).
(See also
<span class="citerefentry"><span class="refentrytitle">times</span>(2)</span>).
</p></dd><dt><span class="term">(17) <span class="emphasis"><em>cstime</em></span> %ld</span></dt><dd><p>
Amount of time that this process's waited-for children
have been scheduled in kernel mode, measured in clock
ticks (divide by <code class="literal">sysconf(_SC_CLK_TCK)</code>).
</p></dd><dt><span class="term">(18) <span class="emphasis"><em>priority</em></span> %ld</span></dt><dd><p>
For processes running a real-time scheduling policy
(<span class="emphasis"><em>policy</em></span> below; see
<span class="citerefentry"><span class="refentrytitle">sched_setscheduler</span>(2)</span>),
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
(<span class="citerefentry"><span class="refentrytitle">setpriority</span>(2)</span>)
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.
</p></dd><dt><span class="term">(19) <span class="emphasis"><em>nice</em></span> %ld</span></dt><dd><p>
The nice value (see
<span class="citerefentry"><span class="refentrytitle">setpriority</span>(2)</span>), a value in the range 19 (low priority)
to -20 (high priority).
</p></dd><dt><span class="term">(20) <span class="emphasis"><em>num_threads</em></span> %ld</span></dt><dd><p>
Number of threads in this process. Currently shown as 0.
</p></dd><dt><span class="term">(21) <span class="emphasis"><em>itrealvalue</em></span> %ld</span></dt><dd><p>
The time in jiffies before the next
<code class="literal">SIGALRM</code>
is sent to the process due to an interval timer.
This field is no longer maintained, and is hard coded as 0.
</p></dd><dt><span class="term">(22) <span class="emphasis"><em>starttime</em></span> %llu</span></dt><dd><p>
The time the process started after system boot.
The value is expressed in clock ticks (divide by
<code class="literal">sysconf(_SC_CLK_TCK)</code>).
</p></dd><dt><span class="term">(23) <span class="emphasis"><em>vsize</em></span> %lu</span></dt><dd><p>Virtual memory size in bytes.</p></dd><dt><span class="term">(24) <span class="emphasis"><em>rss</em></span> %ld</span></dt><dd><p>
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.
</p></dd><dt><span class="term">(25) <span class="emphasis"><em>rsslim</em></span> %lu</span></dt><dd><p>
Current soft limit in bytes on the rss of the process; see
the description of <code class="literal">RLIMIT_RSS</code> in
<span class="citerefentry"><span class="refentrytitle">getrlimit</span>(2)</span>.
</p></dd></dl></div></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/statm</code></span></dt><dd><p>
Provides information about memory usage, measured in pages.
The columns are:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">(1) size</span></dt><dd><p>total program size
(same as VmSize in <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/status</code>)</p></dd><dt><span class="term">(2) resident</span></dt><dd><p>resident set size
(same as VmRSS in <code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/status</code>)</p></dd><dt><span class="term">(3) shared</span></dt><dd><p>number of resident shared pages
(i.e., backed by a file) (same as RssFile+RssShmem in
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/status</code>)</p></dd><dt><span class="term">(4) text</span></dt><dd><p>text (code)</p></dd><dt><span class="term">(5) lib</span></dt><dd><p>library</p></dd><dt><span class="term">(6) data</span></dt><dd><p>data + stack</p></dd><dt><span class="term">(7) dt</span></dt><dd><p>dirty pages (always 0)</p></dd></dl></div><p>
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/status</code></span></dt><dd><p>
Provides much of the information in
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/stat</code> and
<code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/statm</code>
in a format that's easier for humans to parse.
Here's an example:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>cat /proc/$$/status</code></strong>
<code class="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
</code>
</pre><p>
</p><p>The fields are as follows:
</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
<span class="emphasis"><em>Name</em></span>:
Command run by this process.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>Umask</em></span>:
Process umask, expressed in octal with a leading zero; see
<span class="citerefentry"><span class="refentrytitle">umask</span>(2)</span>.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>State</em></span>:
Current state of the process.
One of:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">R</span></dt><dd><p>runnable</p></dd><dt><span class="term">O</span></dt><dd><p>running</p></dd><dt><span class="term">S</span></dt><dd><p>sleeping</p></dd><dt><span class="term">D</span></dt><dd><p>disk sleep</p></dd><dt><span class="term">T</span></dt><dd><p>stopped or tracing stop</p></dd><dt><span class="term">Z</span></dt><dd><p>zombie</p></dd></dl></div><p>
</p></li><li class="listitem"><p>
<span class="emphasis"><em>Tgid</em></span>:
Thread group id (i.e., Process id).
</p></li><li class="listitem"><p>
<span class="emphasis"><em>Pid</em></span>:
Thread id (see
<span class="citerefentry"><span class="refentrytitle">gettid</span>(2)</span>).
</p></li><li class="listitem"><p>
<span class="emphasis"><em>PPid</em></span>:
PID of parent process.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>Uid</em></span>,
<span class="emphasis"><em>Gid</em></span>:
Real, effective, saved set, and filesystem UIDs (GIDs).
</p></li><li class="listitem"><p>
<span class="emphasis"><em>VmSize</em></span>:
Virtual memory size.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>VmLck</em></span>:
Locked memory size (see
<span class="citerefentry"><span class="refentrytitle">mlock</span>(2)</span>).
</p></li><li class="listitem"><p>
<span class="emphasis"><em>VmRSS</em></span>:
Resident set size.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>VmData</em></span>,
<span class="emphasis"><em>VmStk</em></span>,
<span class="emphasis"><em>VmExe</em></span>:
Size of data, stack, and text segments.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>VmLib</em></span>:
Shared library code size.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>SigPnd</em></span>:
Number of signals pending for process as a whole (see
<span class="citerefentry"><span class="refentrytitle">pthreads</span>(7)</span> and
<span class="citerefentry"><span class="refentrytitle">signal</span>(7)</span>).
</p></li><li class="listitem"><p>
<span class="emphasis"><em>SigBlk</em></span>,
<span class="emphasis"><em>SigIgn</em></span>:
Masks indicating signals being blocked and ignored (see
<span class="citerefentry"><span class="refentrytitle">signal</span>(7)</span>).
</p></li></ul></div><p>
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/uid</code></span></dt><dd><p>
This read-only file contains the user id for the process.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/winexename</code></span></dt><dd><p>
This read-only file contains the Windows pathname of the
executed command.
</p></dd><dt><span class="term"><code class="filename">/proc/<span class="emphasis"><em>[pid]</em></span>/winpid</code></span></dt><dd><p>
This read-only file contains the Windows process id for the
process.
</p></dd><dt><span class="term"><code class="filename">/proc/cpuinfo</code></span></dt><dd><p>
This is a collection of CPU and system architecture dependent
items, for each supported architecture a different list.
Two common entries are <span class="emphasis"><em>processor</em></span>
which gives CPU number and
<span class="emphasis"><em>bogomips</em></span>, a system constant
that is calculated during kernel initialization.
SMP machines have information for each CPU.
The
<span class="citerefentry"><span class="refentrytitle">lscpu</span>(1)</span>
command gathers its information from this file.
</p></dd><dt><span class="term"><code class="filename">/proc/cygdrive</code></span></dt><dd><p>
This file is a symbolic link that points to the user's
Windows mapped drive mount point, similar to
<span class="emphasis"><em>root</em></span>.
</p></dd><dt><span class="term"><code class="filename">/proc/devices</code></span></dt><dd><p>
Text listing of major numbers and device groups.
This can be used by <span class="command"><strong>makedev</strong></span>
scripts for consistency with the system.
</p></dd><dt><span class="term"><code class="filename">/proc/filesystems</code></span></dt><dd><p>
A text listing of the filesystems which are supported by Cygwin.
(See also
<span class="citerefentry"><span class="refentrytitle">filesystems</span>(5)</span>.)
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).
</p></dd><dt><span class="term"><code class="filename">/proc/loadavg</code></span></dt><dd><p>
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
<span class="citerefentry"><span class="refentrytitle">uptime</span>(1)</span> 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.
</p></dd><dt><span class="term"><code class="filename">/proc/meminfo</code></span></dt><dd><p>
This file reports statistics about memory usage on the system.
It is used by
<span class="citerefentry"><span class="refentrytitle">free</span>(1)</span>
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.
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><span class="emphasis"><em>MemTotal</em></span> %lu</span></dt><dd><p>
Total usable RAM (i.e., physical RAM minus a few reserved
bits and the system binary code).
</p></dd><dt><span class="term"><span class="emphasis"><em>MemFree</em></span> %lu</span></dt><dd><p>
The sum of <span class="emphasis"><em>LowFree</em></span> +
<span class="emphasis"><em>HighFree</em></span>.
</p></dd><dt><span class="term"><span class="emphasis"><em>HighTotal</em></span> %lu</span></dt><dd><p>Total amount of highmem.</p></dd><dt><span class="term"><span class="emphasis"><em>HighFree</em></span> %lu</span></dt><dd><p>Amount of free highmem.</p></dd><dt><span class="term"><span class="emphasis"><em>LowTotal</em></span> %lu</span></dt><dd><p>
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.
</p></dd><dt><span class="term"><span class="emphasis"><em>LowFree</em></span> %lu</span></dt><dd><p>Amount of free lowmem.</p></dd><dt><span class="term"><span class="emphasis"><em>SwapTotal</em></span> %lu</span></dt><dd><p>Total amount of swap space available.</p></dd><dt><span class="term"><span class="emphasis"><em>SwapFree</em></span> %lu</span></dt><dd><p>Amount of swap space that is currently unused.</p></dd></dl></div></dd><dt><span class="term"><code class="filename">/proc/misc</code></span></dt><dd><p>
Text listing of minor device numbers and names of devices with
major device number of the <code class="literal">misc</code> device group.
This can be used by <span class="command"><strong>makedev</strong></span> scripts
for consistency with the system.
</p></dd><dt><span class="term"><code class="filename">/proc/mounts</code></span></dt><dd><p>
With the introduction of per-process mount namespaces, this file
became a link to
<code class="filename">/proc/self/mounts</code>,
which lists the mount points of the process's own mount
namespace.
The format of this file is documented in
<span class="citerefentry"><span class="refentrytitle">fstab</span>(5)</span>.
</p></dd><dt><span class="term"><code class="filename">/proc/net</code></span></dt><dd><p>
This directory contains various files and subdirectories
containing information about the networking layer.
The files contain ASCII structures and are, therefore, readable
with
<span class="citerefentry"><span class="refentrytitle">cat</span>(1)</span>.
However, the standard
<span class="citerefentry"><span class="refentrytitle">netstat</span>(8)</span>
suite provides much cleaner access to these files.
</p></dd><dt><span class="term"><code class="filename">/proc/net/if_inet6</code></span></dt><dd><p>
This file contains information about IP V6 interface adapters,
if used.
Each line represents an IP V6 interface adapter.
</p><pre class="screen">
<code class="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)
</code>
</pre><p>The fields in each line are:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">(1)</span></dt><dd><p>The IP V6 address of the interface adapter.</p></dd><dt><span class="term">(2)</span></dt><dd><p>The IP V6 interface adapter index.</p></dd><dt><span class="term">(3)</span></dt><dd><p>
The prefix length of the IP V6 interface address.
</p></dd><dt><span class="term">(4)</span></dt><dd><p>The scope of the IP V6 interface address.</p></dd><dt><span class="term">(5)</span></dt><dd><p>The state of the IP V6 interface address.</p></dd><dt><span class="term">(6)</span></dt><dd><p>
The DUID/GUID/UUID of the IP V6 interface adapter.
</p></dd></dl></div><p>
</p><p>
The last number exists only for compatibility reasons and is
always 1.
</p><p>
</p></dd><dt><span class="term"><code class="filename">/proc/partitions</code></span></dt><dd><p>
Contains the major and minor numbers of each partition as well
as the number of 1024-byte blocks and the partition name.
</p></dd><dt><span class="term"><code class="filename">/proc/registry</code></span></dt><dd><p>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/registry32</code></span></dt><dd><p>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/registry64</code></span></dt><dd><p>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/self</code></span></dt><dd><p>
This directory refers to the process accessing the
<code class="filename">/proc</code> filesystem, and is identical to the
<code class="filename">/proc</code> directory named by the process id
of the same process.
</p></dd><dt><span class="term"><code class="filename">/proc/stat</code></span></dt><dd><p>
system statistics.
Varies with architecture.
Common entries include:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><span class="emphasis"><em>cpu 10132153 0 3084719 46828483</em></span></span></dt><dd></dd><dt><span class="term"><span class="emphasis"><em>cpu0 1393280 0 572056 13343292</em></span></span></dt><dd><p>
The amount of time, measured in units of USER_HZ
(1/100ths of a second on most architectures, use
<code class="literal">sysconf(_SC_CLK_TCK)</code>
to obtain the right value), that the system ("cpu"
line) or the specific CPU
("cpu <span class="emphasis"><em>N</em></span>" line)
spent in various states:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">(1) <span class="emphasis"><em>user</em></span></span></dt><dd><p>Time spent in user mode.</p></dd><dt><span class="term">(2) <span class="emphasis"><em>nice</em></span></span></dt><dd><p>
Time spent in user mode with low priority
(nice).
</p></dd><dt><span class="term">(3) <span class="emphasis"><em>system</em></span></span></dt><dd><p>Time spent in system mode.</p></dd><dt><span class="term">(4) <span class="emphasis"><em>idle</em></span></span></dt><dd><p>Time spent in the idle task.</p></dd></dl></div><p>
</p></dd><dt><span class="term"><span class="emphasis"><em>page 5741 1808</em></span></span></dt><dd><p>
The number of pages the system paged in and the number
that were paged out (from disk).
</p></dd><dt><span class="term"><span class="emphasis"><em>swap 1 0</em></span></span></dt><dd><p>
The number of swap pages that have been brought in and
out.
</p></dd><dt><span class="term"><span class="emphasis"><em>intr 1462898</em></span></span></dt><dd><p>The number of interrupts serviced.</p></dd><dt><span class="term"><span class="emphasis"><em>ctxt 115315</em></span></span></dt><dd><p>
The number of context switches that the system
underwent.
</p></dd><dt><span class="term"><span class="emphasis"><em>btime 769041601</em></span></span></dt><dd><p>
boot time, in seconds since the Epoch,
1970-01-01 00:00:00 +0000 (UTC).
</p></dd></dl></div><p>
</p></dd><dt><span class="term"><code class="filename">/proc/swaps</code></span></dt><dd><p>
Swap areas in use.
See also
<span class="citerefentry"><span class="refentrytitle">swapon</span>(8)</span>.
</p></dd><dt><span class="term"><code class="filename">/proc/sys</code></span></dt><dd><p>
This directory contains a number of files and subdirectories
linking to Windows objects, which can be read using these
entries.
</p><p>
String values may be terminated by either '\0'
or '\n'.
</p><p>
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'.
</p></dd><dt><span class="term"><code class="filename">/proc/sysvipc</code></span></dt><dd><p>
Subdirectory containing the pseudo-files
<code class="filename">msg</code>, <code class="filename">sem</code>and
<code class="filename">shm</code>.
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
<span class="citerefentry"><span class="refentrytitle">ipcs</span>(1)</span>.
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.
<span class="citerefentry"><span class="refentrytitle">svipc</span>(7)</span>
provides further background on the information shown by these
files.
</p></dd><dt><span class="term"><code class="filename">/proc/uptime</code></span></dt><dd><p>
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.
</p></dd><dt><span class="term"><code class="filename">/proc/version</code></span></dt><dd><p>
This string identifies the Cygwin version that is currently
running.
For example:
</p><pre class="screen">
<code class="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
</code>
</pre><p>
</p></dd></dl></div></div></div><div class="refsect1"><a name="proc-notes"></a><h2>Notes</h2><p>
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:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>cat -A <span class="emphasis"><em>file</em></span></code></strong>
</pre><p>
</p><p>
This manual page is incomplete, possibly inaccurate, and is the kind
of thing that needs to be updated very often.
</p></div><div class="refsect1"><a name="proc-see_also"></a><h2>See Also</h2><p>
<span class="citerefentry"><span class="refentrytitle">cat</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">find</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">free</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">pstree</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">tr</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">uptime</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">chroot</span>(2)</span>,
<span class="citerefentry"><span class="refentrytitle">mmap</span>(2)</span>,
<span class="citerefentry"><span class="refentrytitle">readlink</span>(2)</span>,
<span class="citerefentry"><span class="refentrytitle">syslog</span>(2)</span>,
<span class="citerefentry"><span class="refentrytitle">hier</span>(7)</span>,
<span class="citerefentry"><span class="refentrytitle">arp</span>(8)</span>,
<span class="citerefentry"><span class="refentrytitle">mount</span>(8)</span>,
<span class="citerefentry"><span class="refentrytitle">netstat</span>(8)</span>,
<span class="citerefentry"><span class="refentrytitle">route</span>(8)</span>.
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