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1 <?xml version="1.0"?>
2 <!--*-nxml-*-->
3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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7   Copyright 2010 Brandon Philips
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22 <refentry id="tmpfiles.d">
23
24         <refentryinfo>
25                 <title>tmpfiles.d</title>
26                 <productname>systemd</productname>
27
28                 <authorgroup>
29                         <author>
30                                 <contrib>Documentation</contrib>
31                                 <firstname>Brandon</firstname>
32                                 <surname>Philips</surname>
33                                 <email>brandon@ifup.org</email>
34                         </author>
35                 </authorgroup>
36         </refentryinfo>
37
38         <refmeta>
39                 <refentrytitle>tmpfiles.d</refentrytitle>
40                 <manvolnum>5</manvolnum>
41         </refmeta>
42
43         <refnamediv>
44                 <refname>tmpfiles.d</refname>
45                 <refpurpose>Configuration for creation, deletion and
46                 cleaning of volatile and temporary files</refpurpose>
47         </refnamediv>
48
49         <refsynopsisdiv>
50                 <para><filename>/etc/tmpfiles.d/*.conf</filename></para>
51                 <para><filename>/run/tmpfiles.d/*.conf</filename></para>
52                 <para><filename>/usr/lib/tmpfiles.d/*.conf</filename></para>
53         </refsynopsisdiv>
54
55         <refsect1>
56                 <title>Description</title>
57
58                 <para><command>systemd-tmpfiles</command> uses the
59                 configuration files from the above directories to describe the
60                 creation, cleaning and removal of volatile and
61                 temporary files and directories which usually reside
62                 in directories such as <filename>/run</filename>
63                 or <filename>/tmp</filename>.</para>
64         </refsect1>
65
66         <refsect1>
67                 <title>Configuration Format</title>
68
69                 <para>Each configuration file shall be named in the
70                 style of <filename>&lt;program&gt;.conf</filename>.
71                 Files in <filename>/etc/</filename> override files
72                 with the same name in <filename>/usr/lib/</filename>
73                 and <filename>/run/</filename>.  Files in
74                 <filename>/run/</filename> override files with the same
75                 name in <filename>/usr/lib/</filename>. Packages
76                 should install their configuration files in
77                 <filename>/usr/lib/</filename>. Files in
78                 <filename>/etc/</filename> are reserved for the local
79                 administrator, who may use this logic to override the
80                 configuration files installed by vendor packages. All
81                 configuration files are sorted by their filename in
82                 alphabetical order, regardless in which of the
83                 directories they reside, to guarantee that a specific
84                 configuration file takes precedence over another file
85                 with an alphabetically later name.</para>
86
87                 <para>If the administrator wants to disable a
88                 configuration file supplied by the vendor the
89                 recommended way is to place a symlink to
90                 <filename>/dev/null</filename> in
91                 <filename>/etc/tmpfiles.d/</filename> bearing the
92                 same filename.</para>
93
94                 <para>The configuration format is one line per path
95                 containing action, path, mode, ownership, age and argument
96                 fields:</para>
97
98                 <programlisting>Type Path        Mode UID  GID  Age Argument
99 d    /run/user   0755 root root 10d -
100 L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
101
102                 <refsect2>
103                         <title>Type</title>
104                         <variablelist>
105                                 <varlistentry>
106                                         <term><varname>f</varname></term>
107                                         <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>
108                                 </varlistentry>
109
110                                 <varlistentry>
111                                         <term><varname>F</varname></term>
112                                         <listitem><para>Create or truncate a file (optionally writing a short string into it, if the argument parameter is passed)</para></listitem>
113                                 </varlistentry>
114
115                                 <varlistentry>
116                                         <term><varname>w</varname></term>
117                                         <listitem><para>Write the argument parameter to a file, if the file exists.
118                                             Lines of this type accept shell-style globs in place of normal path
119                                             names. The argument parameter will be written without a trailing
120                                             newline. C-style backslash escapes are interpreted.</para></listitem>
121                                 </varlistentry>
122
123                                 <varlistentry>
124                                         <term><varname>d</varname></term>
125                                         <listitem><para>Create a directory if it doesn't exist yet</para></listitem>
126                                 </varlistentry>
127
128                                 <varlistentry>
129                                         <term><varname>D</varname></term>
130                                         <listitem><para>Create or empty a directory</para></listitem>
131                                 </varlistentry>
132
133                                 <varlistentry>
134                                         <term><varname>p</varname></term>
135                                         <listitem><para>Create a named pipe (FIFO) if it doesn't exist yet</para></listitem>
136                                 </varlistentry>
137
138                                 <varlistentry>
139                                         <term><varname>L</varname></term>
140                                         <listitem><para>Create a symlink if it doesn't exist yet</para></listitem>
141                                 </varlistentry>
142
143                                 <varlistentry>
144                                         <term><varname>c</varname></term>
145                                         <listitem><para>Create a character device node if it doesn't exist yet</para></listitem>
146                                 </varlistentry>
147
148                                 <varlistentry>
149                                         <term><varname>b</varname></term>
150                                         <listitem><para>Create a block device node if it doesn't exist yet</para></listitem>
151                                 </varlistentry>
152
153                                 <varlistentry>
154                                         <term><varname>x</varname></term>
155                                         <listitem><para>Ignore a path
156                                         during cleaning. Use this type
157                                         to exclude paths from clean-up
158                                         as controlled with the Age
159                                         parameter. Note that lines of
160                                         this type do not influence the
161                                         effect of r or R lines. Lines
162                                         of this type accept
163                                         shell-style globs in place of
164                                         normal path
165                                         names.</para></listitem>
166                                 </varlistentry>
167
168                                 <varlistentry>
169                                         <term><varname>X</varname></term>
170                                         <listitem><para>Ignore a path
171                                         during cleanup. Use this type
172                                         to prevent path removal as
173                                         controlled with the Age parameter.
174                                         Note that if path is a directory,
175                                         content of a directory is not
176                                         excluded from clean-up, only
177                                         directory itself. Lines of this
178                                         type accept shell-style globs
179                                         in place of normal path
180                                         names.</para></listitem>
181                                 </varlistentry>
182
183                                 <varlistentry>
184                                         <term><varname>r</varname></term>
185                                         <listitem><para>Remove a file
186                                         or directory if it
187                                         exists. This may not be used
188                                         to remove non-empty
189                                         directories, use R for
190                                         that. Lines of this type
191                                         accept shell-style globs in
192                                         place of normal path
193                                         names.</para></listitem>
194                                 </varlistentry>
195
196                                 <varlistentry>
197                                         <term><varname>R</varname></term>
198                                         <listitem><para>Recursively
199                                         remove a path and all its
200                                         subdirectories (if it is a
201                                         directory). Lines of this type
202                                         accept shell-style globs in
203                                         place of normal path
204                                         names.</para></listitem>
205                                 </varlistentry>
206
207                                 <varlistentry>
208                                         <term><varname>z</varname></term>
209                                         <listitem><para>Restore
210                                         SELinux security context label
211                                         and set ownership and access
212                                         mode of a file or directory if
213                                         it exists.  Lines of this type
214                                         accept shell-style globs in
215                                         place of normal path names.
216                                         </para></listitem>
217                                 </varlistentry>
218
219                                 <varlistentry>
220                                         <term><varname>Z</varname></term>
221                                         <listitem><para>Recursively
222                                         restore SELinux security
223                                         context label and set
224                                         ownership and access mode of a
225                                         path and all its
226                                         subdirectories (if it is a
227                                         directory). Lines of this type
228                                         accept shell-style globs in
229                                         place of normal path
230                                         names.</para></listitem>
231                                 </varlistentry>
232                         </variablelist>
233                 </refsect2>
234
235                 <refsect2>
236                         <title>Mode</title>
237
238                         <para>The file access mode to use when
239                         creating this file or directory. If omitted or
240                         when set to - the default is used: 0755 for
241                         directories, 0644 for all other file
242                         objects. For z, Z lines if omitted or when set
243                         to - the file access mode will not be
244                         modified. This parameter is ignored for x, r,
245                         R, L lines.</para>
246                 </refsect2>
247
248                 <refsect2>
249                         <title>UID, GID</title>
250
251                         <para>The user and group to use for this file
252                         or directory. This may either be a numeric
253                         user/group ID or a user or group name. If
254                         omitted or when set to - the default 0 (root)
255                         is used. For z, Z lines when omitted or when set to -
256                         the file ownership will not be modified.
257                         These parameters are ignored for x, r, R, L lines.</para>
258                 </refsect2>
259
260                 <refsect2>
261                         <title>Age</title>
262                         <para>The date field, when set, is used to
263                         decide what files to delete when cleaning. If
264                         a file or directory is older than the current
265                         time minus the age field it is deleted. The
266                         field format is a series of integers each
267                         followed by one of the following
268                         postfixes for the respective time units:</para>
269
270                         <variablelist>
271                                 <varlistentry>
272                                 <term><varname>s</varname></term>
273                                 <term><varname>min</varname></term>
274                                 <term><varname>h</varname></term>
275                                 <term><varname>d</varname></term>
276                                 <term><varname>w</varname></term>
277                                 <term><varname>ms</varname></term>
278                                 <term><varname>m</varname></term>
279                                 <term><varname>us</varname></term></varlistentry>
280                         </variablelist>
281
282                         <para>If multiple integers and units are specified the time
283                         values are summed up. If an integer is given without a unit,
284                         s is assumed.
285                         </para>
286
287                         <para>When the age is set to zero, the files are cleaned
288                         unconditionally.</para>
289
290                         <para>The age field only applies to lines starting with
291                         d, D and x. If omitted or set to - no automatic clean-up
292                         is done.</para>
293
294                         <para>If the age field starts with a tilde
295                         character (~) the clean-up is only applied to
296                         files and directories one level inside the
297                         directory specified, but not the files and
298                         directories immediately inside it.</para>
299                 </refsect2>
300
301                 <refsect2>
302                         <title>Argument</title>
303
304                         <para>For L lines determines the destination
305                         path of the symlink. For c, b determines the
306                         major/minor of the device node, with major and
307                         minor formatted as integers, separated by :,
308                         e.g. "1:3". For f, F, w may be used to specify
309                         a short string that is written to the file,
310                         suffixed by a newline. Ignored for all other
311                         lines.</para>
312                 </refsect2>
313
314         </refsect1>
315
316         <refsect1>
317                 <title>Example</title>
318                 <example>
319                         <title>/etc/tmpfiles.d/screen.conf example</title>
320                         <para><command>screen</command> needs two directories created at boot with specific modes and ownership.</para>
321
322                         <programlisting>d /var/run/screens  1777 root root 10d
323 d /var/run/uscreens 0755 root root 10d12h</programlisting>
324                 </example>
325         </refsect1>
326
327         <refsect1>
328                 <title>See Also</title>
329                 <para>
330                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
331                         <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
332                         <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>
333                 </para>
334         </refsect1>
335
336 </refentry>