chiark / gitweb /
journald: move /dev/log socket to /run
[elogind.git] / man / tmpfiles.d.xml
index 75d4bcd695796e6f2e13b03d4721a4c161737581..e54f1ba5c36cb920925c5d301a5367401266f721 100644 (file)
                 temporary files and directories which usually reside
                 in directories such as <filename>/run</filename>
                 or <filename>/tmp</filename>.</para>
                 temporary files and directories which usually reside
                 in directories such as <filename>/run</filename>
                 or <filename>/tmp</filename>.</para>
+
+                <para>Volatile and temporary files and directories are
+                those located in <filename>/run</filename> (and its
+                alias <filename>/var/run</filename>),
+                <filename>/tmp</filename>,
+                <filename>/var/tmp</filename>, the API file systems
+                such as <filename>/sys</filename> or
+                <filename>/proc</filename>, as well as some other
+                directories below <filename>/var</filename>.</para>
+
+                <para>System daemons frequently require private
+                runtime directories below <filename>/run</filename> to
+                place communication sockets and similar in. For these,
+                consider declaring them in their unit files using
+                <varname>RuntimeDirectory=</varname>
+                (see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for details),
+                if this is feasible.</para>
         </refsect1>
 
         <refsect1>
                 <title>Configuration Format</title>
 
                 <para>Each configuration file shall be named in the
         </refsect1>
 
         <refsect1>
                 <title>Configuration Format</title>
 
                 <para>Each configuration file shall be named in the
-                style of <filename>&lt;program&gt;.conf</filename>.
-                Files in <filename>/etc/</filename> override files
-                with the same name in <filename>/usr/lib/</filename>
-                and <filename>/run/</filename>.  Files in
-                <filename>/run/</filename> override files with the same
-                name in <filename>/usr/lib/</filename>. Packages
+                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
                 should install their configuration files in
-                <filename>/usr/lib/</filename>. Files in
-                <filename>/etc/</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
-                alphabetical order, regardless in which of the
-                directories they reside, to guarantee that a specific
-                configuration file takes precedence over another file
-                with an alphabetically later name</para>
+                <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
 
                 <para>If the administrator wants to disable a
-                configuration file supplied by the vendor the
+                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
                 recommended way is to place a symlink to
                 <filename>/dev/null</filename> in
                 <filename>/etc/tmpfiles.d/</filename> bearing the
-                same file name.</para>
+                same filename.</para>
 
                 <para>The configuration format is one line per path
 
                 <para>The configuration format is one line per path
-                containing action, path, mode, ownership, age and argument
+                containing type, path, mode, ownership, age, and argument
                 fields:</para>
 
                 fields:</para>
 
-                <programlisting>Type Path        Mode UID  GID  Age Argument
+                <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>
 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>
                         <variablelist>
                                 <varlistentry>
                                         <term><varname>f</varname></term>
-                                        <listitem><para>Create a file if it doesn't exist yet (optionally writing a short string into it, if the argument parameter is passed)</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>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>F</varname></term>
-                                        <listitem><para>Create or truncate a file (optionally writing a short string into it, if the argument parameter is passed)</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>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>w</varname></term>
-                                        <listitem><para>Write the argument parameter to a file, if it exists.</para></listitem>
+                                        <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>
                                 </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>
                                 </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>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>p</varname></term>
-                                        <listitem><para>Create a named pipe (FIFO) if it doesn't exist yet</para></listitem>
+                                        <listitem><para>Create a named pipe (FIFO) if it does not exist yet.</para></listitem>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>L</varname></term>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>L</varname></term>
-                                        <listitem><para>Create a symlink if it doesn't exist yet</para></listitem>
+                                        <listitem><para>Create a symlink if it does not exist yet.</para></listitem>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>c</varname></term>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>c</varname></term>
-                                        <listitem><para>Create a character device node if it doesn't exist yet</para></listitem>
+                                        <listitem><para>Create a character device node if it does not exist yet.</para></listitem>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>b</varname></term>
                                 </varlistentry>
 
                                 <varlistentry>
                                         <term><varname>b</varname></term>
-                                        <listitem><para>Create a block device node if it doesn't exist yet</para></listitem>
+                                        <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
+                                        security context. If it does not exist, do
+                                        nothing.</para></listitem>
                                 </varlistentry>
 
                                 <varlistentry>
                                 </varlistentry>
 
                                 <varlistentry>
@@ -155,23 +202,45 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                                         as controlled with the Age
                                         parameter. Note that lines of
                                         this type do not influence the
                                         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
                                         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
                                 </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>
 
                                         names.</para></listitem>
                                 </varlistentry>
 
@@ -189,7 +258,7 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                                 <varlistentry>
                                         <term><varname>z</varname></term>
                                         <listitem><para>Restore
                                 <varlistentry>
                                         <term><varname>z</varname></term>
                                         <listitem><para>Restore
-                                        SELinux security context label
+                                        SELinux security context
                                         and set ownership and access
                                         mode of a file or directory if
                                         it exists.  Lines of this type
                                         and set ownership and access
                                         mode of a file or directory if
                                         it exists.  Lines of this type
@@ -202,7 +271,7 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                                         <term><varname>Z</varname></term>
                                         <listitem><para>Recursively
                                         restore SELinux security
                                         <term><varname>Z</varname></term>
                                         <listitem><para>Recursively
                                         restore SELinux security
-                                        context label and set
+                                        context and set
                                         ownership and access mode of a
                                         path and all its
                                         subdirectories (if it is a
                                         ownership and access mode of a
                                         path and all its
                                         subdirectories (if it is a
@@ -212,6 +281,77 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                                         names.</para></listitem>
                                 </varlistentry>
                         </variablelist>
                                         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>
                 </refsect2>
 
                 <refsect2>
@@ -219,12 +359,15 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
 
                         <para>The file access mode to use when
                         creating this file or directory. If omitted or
 
                         <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 all other file
-                        objects. For z, Z lines if omitted or when set
-                        to - the file access mode will not be
-                        modified. This parameter is ignored for x, r,
-                        R, L 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>
                 </refsect2>
 
                 <refsect2>
@@ -233,10 +376,15 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                         <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
                         <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. For z, Z lines when omitted or when set to -
-                        the file ownership will not be modified.
-                        These parameters are ignored for x, r, R, L 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>
                 </refsect2>
 
                 <refsect2>
@@ -244,7 +392,7 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                         <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
                         <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>
                         field format is a series of integers each
                         followed by one of the following
                         postfixes for the respective time units:</para>
@@ -261,25 +409,45 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                                 <term><varname>us</varname></term></varlistentry>
                         </variablelist>
 
                                 <term><varname>us</varname></term></varlistentry>
                         </variablelist>
 
-                        <para>If multiple integers and units are specified the time
-                        values are summed up.</para>
-
-                        <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>
+                        <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>
 
                 <refsect2>
                         <title>Argument</title>
 
                 </refsect2>
 
                 <refsect2>
                         <title>Argument</title>
 
-                        <para>For L lines determines the destination
-                        path of the symlink. For c, b determines the
+                        <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
                         major/minor of the device node, with major and
-                        minor formatted as integers, separated by :,
-                        e.g. "1:3". For f, F, w may be used to specify
-                        a short string that is written to the file,
-                        suffixed by a newline. Ignored for all other
-                        lines.</para>
+                        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>
                 </refsect2>
 
         </refsect1>
@@ -290,8 +458,15 @@ L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
                         <title>/etc/tmpfiles.d/screen.conf example</title>
                         <para><command>screen</command> needs two directories created at boot with specific modes and ownership.</para>
 
                         <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
-d /var/run/uscreens 0755 root root 10d12h</programlisting>
+                        <programlisting>d /run/screens  1777 root root 10d
+d /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>
 
                 </example>
         </refsect1>
 
@@ -299,7 +474,9 @@ d /var/run/uscreens 0755 root root 10d12h</programlisting>
                 <title>See Also</title>
                 <para>
                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                 <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>,
+                        <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 </para>
         </refsect1>
 
                 </para>
         </refsect1>