Copyright 2010 Brandon Philips
systemd is free software; 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
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU General Public License
+ You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="tmpfiles.d">
</refnamediv>
<refsynopsisdiv>
- <para><filename>/usr/lib/tmpfiles.d/*.conf</filename></para>
<para><filename>/etc/tmpfiles.d/*.conf</filename></para>
<para><filename>/run/tmpfiles.d/*.conf</filename></para>
+ <para><filename>/usr/lib/tmpfiles.d/*.conf</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
- <para><command>systemd-tmpfiles</command> uses the
- configuration files from the above directories to describe the
- creation, cleaning and removal of volatile and
- temporary files and directories which usually reside
- in directories such as <filename>/run</filename>
- or <filename>/tmp</filename>.</para>
+ <para><command>systemd-tmpfiles</command> uses the
+ configuration files from the above directories to describe the
+ creation, cleaning and removal of volatile and
+ temporary files and directories which usually reside
+ in directories such as <filename>/run</filename>
+ or <filename>/tmp</filename>.</para>
</refsect1>
<refsect1>
- <title>Configuration Format</title>
-
- <para>Each configuration file is named in the style of
- <filename><program>.conf</filename>.
- Files in <filename>/etc/</filename> overwrite
- files with the same name in <filename>/usr/lib/</filename>.
- Files in <filename>/run</filename> overwrite files with
- the same name in <filename>/etc/</filename> and
- <filename>/usr/lib/</filename>. Packages should install their
- configuration files in <filename>/usr/lib/</filename>, files
- in <filename>/etc/</filename> are reserved for the local
- administration, which possibly decides to overwrite the
- configurations installed from packages. All files are sorted
- by filename in alphabetical order, regardless in which of the
- directories they reside, to ensure that a specific
- configuration file takes precedence over another file with
- an alphabetically later name.</para>
-
- <para>The configuration format is one line per path
- containing action, mode, ownership and age
- fields:</para>
-
- <programlisting>Type Path Mode UID GID Age
-d /run/user 0755 root root 10d</programlisting>
+ <title>Configuration Format</title>
+
+ <para>Each configuration file shall be named in the
+ style of
+ <filename><replaceable>package</replaceable>.conf</filename>
+ or
+ <filename><replaceable>package</replaceable>-<replaceable>part</replaceable>.conf</filename>.
+ The second variant should be used when it is desirable
+ to make it easy to override just this part of
+ configuration.</para>
+
+ <para>Files in <filename>/etc/tmpfiles.d</filename>
+ override files with the same name in
+ <filename>/usr/lib/tmpfiles.d</filename> and
+ <filename>/run/tmpfiles.d</filename>. Files in
+ <filename>/run/tmpfiles.d</filename> override files
+ with the same name in
+ <filename>/usr/lib/tmpfiles.d</filename>. Packages
+ should install their configuration files in
+ <filename>/usr/lib/tmpfiles.d</filename>. Files in
+ <filename>/etc/tmpfiles.d</filename> are reserved for
+ the local administrator, who may use this logic to
+ override the configuration files installed by vendor
+ packages. All configuration files are sorted by their
+ filename in lexicographic order, regardless of which
+ of the directories they reside in. If multiple files
+ specify the same path, the entry in the file with the
+ lexicographically earliest name will be applied, all
+ all other conflicting entries logged as errors.</para>
+
+ <para>If the administrator wants to disable a
+ configuration file supplied by the vendor, the
+ recommended way is to place a symlink to
+ <filename>/dev/null</filename> in
+ <filename>/etc/tmpfiles.d/</filename> bearing the
+ same filename.</para>
+
+ <para>The configuration format is one line per path
+ containing type, path, mode, ownership, age, and argument
+ fields:</para>
+
+ <programlisting>#Type Path Mode UID GID Age Argument
+d /run/user 0755 root root 10d -
+L /tmp/foobar - - - - /dev/null</programlisting>
+
<refsect2>
<title>Type</title>
+
+ <para>The type consists of a single letter and
+ optionally an exclamation mark.</para>
+
+ <para>The following line types are understood:</para>
+
<variablelist>
<varlistentry>
<term><varname>f</varname></term>
- <listitem><para>Create a file if it doesn't exist yet</para></listitem>
+ <listitem><para>Create a file if it does not exist yet. If the argument parameter is given, it will be written to the file.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>F</varname></term>
- <listitem><para>Create or truncate a file</para></listitem>
+ <listitem><para>Create or truncate a file. If the argument parameter is given, it will be written to the file.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>w</varname></term>
+ <listitem><para>Write the argument parameter to a file, if the file exists.
+ Lines of this type accept shell-style globs in place of normal path
+ names. The argument parameter will be written without a trailing
+ newline. C-style backslash escapes are interpreted.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>d</varname></term>
- <listitem><para>Create a directory if it doesn't exist yet</para></listitem>
+ <listitem><para>Create a directory if it does not exist yet.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>D</varname></term>
- <listitem><para>Create or empty a directory</para></listitem>
+ <listitem><para>Create or empty a directory.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>p</varname></term>
+ <listitem><para>Create a named pipe (FIFO) if it does not exist yet.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>L</varname></term>
+ <listitem><para>Create a symlink if it does not exist yet.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>c</varname></term>
+ <listitem><para>Create a character device node if it does not exist yet.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>b</varname></term>
+ <listitem><para>Create a block device node if it does not exist yet.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>m</varname></term>
+ <listitem><para>If the
+ specified file path exists,
+ adjust its access mode, group
+ and user to the specified
+ values and reset the SELinux
+ label. If it does not exist, do
+ nothing.</para></listitem>
</varlistentry>
<varlistentry>
as controlled with the Age
parameter. Note that lines of
this type do not influence the
- effect of r or R lines. Lines
- of this type accept
+ effect of <varname>r</varname>
+ or <varname>R</varname> lines.
+ Lines of this type accept
shell-style globs in place of
- of normal path
- names.</para></listitem>
+ normal path names.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>X</varname></term>
+ <listitem><para>Ignore a path
+ during cleaning. Use this type
+ to exclude paths from clean-up
+ as controlled with the Age
+ parameter. Unlike
+ <varname>x</varname>, this
+ parameter will not exclude the
+ content if path is a
+ directory, but only directory
+ itself. Note that lines of
+ this type do not influence the
+ effect of <varname>r</varname>
+ or <varname>R</varname> lines.
+ Lines of this type accept
+ shell-style globs in place of
+ normal path names.
+ </para></listitem>
</varlistentry>
<varlistentry>
<term><varname>r</varname></term>
<listitem><para>Remove a file
- or directory if it
- exists. This may not be used
- to remove non-empty
- directories, use R for
- that. Lines of this type
- accept shell-style globs in
- place of normal path
+ or directory if it exists.
+ This may not be used to remove
+ non-empty directories, use
+ <varname>R</varname> for that.
+ Lines of this type accept
+ shell-style globs in place of
+ normal path
names.</para></listitem>
</varlistentry>
place of normal path
names.</para></listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><varname>z</varname></term>
+ <listitem><para>Restore
+ SELinux security context label
+ and set ownership and access
+ mode of a file or directory if
+ it exists. Lines of this type
+ accept shell-style globs in
+ place of normal path names.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Z</varname></term>
+ <listitem><para>Recursively
+ restore SELinux security
+ context label and set
+ ownership and access mode of a
+ path and all its
+ subdirectories (if it is a
+ directory). Lines of this type
+ accept shell-style globs in
+ place of normal path
+ names.</para></listitem>
+ </varlistentry>
</variablelist>
+
+ <para>If the exclamation mark is used, this
+ line is only safe of execute during boot, and
+ can break a running system. Lines without the
+ exclamation mark are presumed to be safe to
+ execute at any time, e.g. on package upgrades.
+ <command>systemd-tmpfiles</command> will
+ execute line with an exclamation mark only if
+ option <option>--boot</option> is given.
+ </para>
+
+ <para>For example:
+ <programlisting>
+# Make sure these are created by default so that nobody else can
+d /tmp/.X11-unix 1777 root root 10d
+
+# Unlink the X11 lock files
+r! /tmp/.X[0-9]*-lock
+ </programlisting>
+ The second line in contrast to the first one
+ would break a running system, and will only be
+ executed with <option>--boot</option>.</para>
+ </refsect2>
+
+ <refsect2>
+ <title>Path</title>
+
+ <para>The file system path specification supports simple specifier
+ expansion. The following expansions are
+ understood:</para>
+
+ <table>
+ <title>Specifiers available</title>
+ <tgroup cols='3' align='left' colsep='1' rowsep='1'>
+ <colspec colname="spec" />
+ <colspec colname="mean" />
+ <colspec colname="detail" />
+ <thead>
+ <row>
+ <entry>Specifier</entry>
+ <entry>Meaning</entry>
+ <entry>Details</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>%m</literal></entry>
+ <entry>Machine ID</entry>
+ <entry>The machine ID of the running system, formatted as string. See <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information.</entry>
+ </row>
+ <row>
+ <entry><literal>%b</literal></entry>
+ <entry>Boot ID</entry>
+ <entry>The boot ID of the running system, formatted as string. See <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry> for more information.</entry>
+ </row>
+ <row>
+ <entry><literal>%H</literal></entry>
+ <entry>Host name</entry>
+ <entry>The hostname of the running system.</entry>
+ </row>
+ <row>
+ <entry><literal>%v</literal></entry>
+ <entry>Kernel release</entry>
+ <entry>Identical to <command>uname -r</command> output.</entry>
+ </row>
+ <row>
+ <entry><literal>%%</literal></entry>
+ <entry>Escaped %</entry>
+ <entry>Single percent sign.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
</refsect2>
<refsect2>
<para>The file access mode to use when
creating this file or directory. If omitted or
- when set to - the default is used: 0755 for
- directories, 0644 for files. This parameter is
- ignored for x, r, R lines.</para>
+ when set to -, the default is used: 0755 for
+ directories, 0644 for all other file objects.
+ For <varname>z</varname>, <varname>Z</varname>
+ lines, if omitted or when set to
+ <literal>-</literal>, the file access mode
+ will not be modified. This parameter is
+ ignored for <varname>x</varname>,
+ <varname>r</varname>, <varname>R</varname>,
+ <varname>L</varname> lines.</para>
</refsect2>
<refsect2>
<para>The user and group to use for this file
or directory. This may either be a numeric
user/group ID or a user or group name. If
- omitted or when set to - the default 0 (root)
- is used. . These parameters are ignored for x,
- r, R lines.</para>
+ omitted or when set to <literal>-</literal>,
+ the default 0 (root) is used. For
+ <varname>z</varname>, <varname>Z</varname>
+ lines, when omitted or when set to -, the file
+ ownership will not be modified. These
+ parameters are ignored for
+ <varname>x</varname>, <varname>r</varname>,
+ <varname>R</varname>, <varname>L</varname>
+ lines.</para>
</refsect2>
<refsect2>
<para>The date field, when set, is used to
decide what files to delete when cleaning. If
a file or directory is older than the current
- time minus the age field it is deleted. The
+ time minus the age field, it is deleted. The
field format is a series of integers each
followed by one of the following
postfixes for the respective time units:</para>
<term><varname>us</varname></term></varlistentry>
</variablelist>
- <para>If multiple integers and units are specified the time
- values are summed up.</para>
+ <para>If multiple integers and units are specified, the time
+ values are summed up. If an integer is given without a unit,
+ s is assumed.
+ </para>
+
+ <para>When the age is set to zero, the files are cleaned
+ unconditionally.</para>
+
+ <para>The age field only applies to lines
+ starting with <varname>d</varname>,
+ <varname>D</varname>, and
+ <varname>x</varname>. If omitted or set to
+ <literal>-</literal>, no automatic clean-up is
+ done.</para>
+
+ <para>If the age field starts with a tilde
+ character <literal>~</literal>, the clean-up
+ is only applied to files and directories one
+ level inside the directory specified, but not
+ the files and directories immediately inside
+ it.</para>
+ </refsect2>
- <para>The age field only applies to lines starting with
- d, D and x. If omitted or set to - no automatic clean-up
- is done.</para>
+ <refsect2>
+ <title>Argument</title>
+
+ <para>For <varname>L</varname> lines
+ determines the destination path of the
+ symlink. For <varname>c</varname>,
+ <varname>b</varname> determines the
+ major/minor of the device node, with major and
+ minor formatted as integers, separated by
+ <literal>:</literal>, e.g.
+ <literal>1:3</literal>. For
+ <varname>f</varname>, <varname>F</varname>,
+ and <varname>w</varname> may be used to
+ specify a short string that is written to the
+ file, suffixed by a newline. Ignored for all
+ other lines.</para>
</refsect2>
</refsect1>
<title>/etc/tmpfiles.d/screen.conf example</title>
<para><command>screen</command> needs two directories created at boot with specific modes and ownership.</para>
- <programlisting>d /var/run/screens 1777 root root 10d
+ <programlisting>d /var/run/screens 1777 root root 10d
d /var/run/uscreens 0755 root root 10d12h</programlisting>
</example>
+ <example>
+ <title>/etc/tmpfiles.d/abrt.conf example</title>
+ <para><command>abrt</command> needs a directory created at boot with specific mode and ownership and its content should be preserved.</para>
+
+ <programlisting>d /var/tmp/abrt 0755 abrt abrt
+x /var/tmp/abrt/*</programlisting>
+ </example>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>