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
- style of <filename><program>.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
- <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 other conflicting entries will be logged as
+ errors. When two lines are prefix and suffix of each
+ other, then the prefix is always processed first, the
+ suffix later. Otherwise, the files/directories are
+ processed in the order they are listed.</para>
<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
- same file name.</para>
+ same filename.</para>
<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>
- <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>
+
+ <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 (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>
- <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>
- <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>
- <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 doesn't exist yet</para></listitem>
+ <term><varname>p+</varname></term>
+ <listitem><para>Create a named
+ pipe (FIFO) if it does not
+ exist yet. If suffixed with
+ <varname>+</varname> and a
+ file already exists where the
+ pipe is to be created, it will
+ be removed and be replaced by
+ the pipe.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>L</varname></term>
- <listitem><para>Create a symlink if it doesn't exist yet</para></listitem>
+ <term><varname>L+</varname></term>
+ <listitem><para>Create a
+ symlink if it does not exist
+ yet. If suffixed with
+ <varname>+</varname> and a
+ file already exists where the
+ symlink is to be created, it
+ will be removed and be
+ replaced by the
+ symlink. If the argument is omitted,
+ symlinks to files with the same name
+ residing in the directory
+ <filename>/usr/share/factory/</filename>
+ are created.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>c</varname></term>
- <listitem><para>Create a character device node if it doesn't exist yet</para></listitem>
+ <term><varname>c+</varname></term>
+ <listitem><para>Create a
+ character device node if it
+ does not exist yet. If
+ suffixed with
+ <varname>+</varname> and a
+ file already exists where the
+ device node is to be created,
+ it will be removed and be
+ replaced by the device
+ node. It is recommended to suffix this
+ entry with an exclamation mark to only
+ create static device nodes at boot,
+ as udev will not manage static device
+ nodes that are created at runtime.
+ </para></listitem>
</varlistentry>
<varlistentry>
<term><varname>b</varname></term>
- <listitem><para>Create a block device node if it doesn't exist yet</para></listitem>
+ <term><varname>b+</varname></term>
+ <listitem><para>Create a block
+ device node if it does not
+ exist yet. If suffixed with
+ <varname>+</varname> and a
+ file already exists where the
+ device node is to be created,
+ it will be removed and be
+ replaced by the device
+ node. It is recommended to suffix this
+ entry with an exclamation mark to only
+ create static device nodes at boot,
+ as udev will not manage static device
+ nodes that are created at runtime.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>C</varname></term>
+ <listitem><para>Recursively
+ copy a file or directory, if
+ the destination files or
+ directories do not exist
+ yet. Note that this command
+ will not descend into
+ subdirectories if the
+ destination directory already
+ exists. Instead, the entire
+ copy operation is
+ skipped. If the argument is omitted,
+ files from the source directory
+ <filename>/usr/share/factory/</filename>
+ with the same name are copied.</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>
<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.
+ <listitem><para>Adjust the
+ access mode, group and user,
+ and restore the SELinux security
+ context 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
+ set the access mode, group and
+ user, and restore the SELinux
+ security context of a file or
+ directory if it exists, as
+ well as of its subdirectories
+ and the files contained
+ therein (if applicable). 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 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>
+
+ <para>Optionally, if prefixed with
+ <literal>~</literal>, the access mode is masked
+ based on the already set access bits for
+ existing file or directories: if the existing
+ file has all executable bits unset, all
+ executable bits are removed from the new
+ access mode, too. Similarly, if all read bits
+ are removed from the old access mode, they will
+ be removed from the new access mode too, and
+ if all write bits are removed, they will be
+ removed from the new access mode too. In
+ addition, the sticky/SUID/SGID bit is removed unless
+ applied to a directory. This
+ functionality is particularly useful in
+ conjunction with <varname>Z</varname>.</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. 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>
<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
- d, D and x. If omitted or set to - no automatic clean-up
- is done.</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 (~) 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>
+ 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>
- <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
- 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
+ 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. For
+ <varname>C</varname>, specifies the source file
+ or directory. Ignored for all other
lines.</para>
</refsect2>
<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>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff