man/tmpfiles.d.xml

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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 file name.</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                                         of normal path
 165                                         names.</para></listitem>
 166                                 </varlistentry>
 167
 168                                 <varlistentry>
 169                                         <term><varname>r</varname></term>
 170                                         <listitem><para>Remove a file
 171                                         or directory if it
 172                                         exists. This may not be used
 173                                         to remove non-empty
 174                                         directories, use R for
 175                                         that. Lines of this type
 176                                         accept shell-style globs in
 177                                         place of normal path
 178                                         names.</para></listitem>
 179                                 </varlistentry>
 180
 181                                 <varlistentry>
 182                                         <term><varname>R</varname></term>
 183                                         <listitem><para>Recursively
 184                                         remove a path and all its
 185                                         subdirectories (if it is a
 186                                         directory). Lines of this type
 187                                         accept shell-style globs in
 188                                         place of normal path
 189                                         names.</para></listitem>
 190                                 </varlistentry>
 191
 192                                 <varlistentry>
 193                                         <term><varname>z</varname></term>
 194                                         <listitem><para>Restore
 195                                         SELinux security context label
 196                                         and set ownership and access
 197                                         mode of a file or directory if
 198                                         it exists.  Lines of this type
 199                                         accept shell-style globs in
 200                                         place of normal path names.
 201                                         </para></listitem>
 202                                 </varlistentry>
 203
 204                                 <varlistentry>
 205                                         <term><varname>Z</varname></term>
 206                                         <listitem><para>Recursively
 207                                         restore SELinux security
 208                                         context label and set
 209                                         ownership and access mode of a
 210                                         path and all its
 211                                         subdirectories (if it is a
 212                                         directory). Lines of this type
 213                                         accept shell-style globs in
 214                                         place of normal path
 215                                         names.</para></listitem>
 216                                 </varlistentry>
 217                         </variablelist>
 218                 </refsect2>
 219
 220                 <refsect2>
 221                         <title>Mode</title>
 222
 223                         <para>The file access mode to use when
 224                         creating this file or directory. If omitted or
 225                         when set to - the default is used: 0755 for
 226                         directories, 0644 for all other file
 227                         objects. For z, Z lines if omitted or when set
 228                         to - the file access mode will not be
 229                         modified. This parameter is ignored for x, r,
 230                         R, L lines.</para>
 231                 </refsect2>
 232
 233                 <refsect2>
 234                         <title>UID, GID</title>
 235
 236                         <para>The user and group to use for this file
 237                         or directory. This may either be a numeric
 238                         user/group ID or a user or group name. If
 239                         omitted or when set to - the default 0 (root)
 240                         is used. For z, Z lines when omitted or when set to -
 241                         the file ownership will not be modified.
 242                         These parameters are ignored for x, r, R, L lines.</para>
 243                 </refsect2>
 244
 245                 <refsect2>
 246                         <title>Age</title>
 247                         <para>The date field, when set, is used to
 248                         decide what files to delete when cleaning. If
 249                         a file or directory is older than the current
 250                         time minus the age field it is deleted. The
 251                         field format is a series of integers each
 252                         followed by one of the following
 253                         postfixes for the respective time units:</para>
 254
 255                         <variablelist>
 256                                 <varlistentry>
 257                                 <term><varname>s</varname></term>
 258                                 <term><varname>min</varname></term>
 259                                 <term><varname>h</varname></term>
 260                                 <term><varname>d</varname></term>
 261                                 <term><varname>w</varname></term>
 262                                 <term><varname>ms</varname></term>
 263                                 <term><varname>m</varname></term>
 264                                 <term><varname>us</varname></term></varlistentry>
 265                         </variablelist>
 266
 267                         <para>If multiple integers and units are specified the time
 268                         values are summed up. If an integer is given without a unit,
 269                         s is assumed.
 270                         </para>
 271
 272                         <para>When the age is set to zero, the files are cleaned
 273                         unconditionally.</para>
 274
 275                         <para>The age field only applies to lines starting with
 276                         d, D and x. If omitted or set to - no automatic clean-up
 277                         is done.</para>
 278
 279                         <para>If the age field starts with a tilde
 280                         character (~) the clean-up is only applied to
 281                         files and directories one level inside the
 282                         directory specified, but not the files and
 283                         directories immediately inside it.</para>
 284                 </refsect2>
 285
 286                 <refsect2>
 287                         <title>Argument</title>
 288
 289                         <para>For L lines determines the destination
 290                         path of the symlink. For c, b determines the
 291                         major/minor of the device node, with major and
 292                         minor formatted as integers, separated by :,
 293                         e.g. "1:3". For f, F, w may be used to specify
 294                         a short string that is written to the file,
 295                         suffixed by a newline. Ignored for all other
 296                         lines.</para>
 297                 </refsect2>
 298
 299         </refsect1>
 300
 301         <refsect1>
 302                 <title>Example</title>
 303                 <example>
 304                         <title>/etc/tmpfiles.d/screen.conf example</title>
 305                         <para><command>screen</command> needs two directories created at boot with specific modes and ownership.</para>
 306
 307                         <programlisting>d /var/run/screens  1777 root root 10d
 308 d /var/run/uscreens 0755 root root 10d12h</programlisting>
 309                 </example>
 310         </refsect1>
 311
 312         <refsect1>
 313                 <title>See Also</title>
 314                 <para>
 315                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 316                         <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 317                         <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 318                 </para>
 319         </refsect1>
 320
 321 </refentry>