man/tmpfiles.d.xml

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   6   Copyright 2010 Brandon Philips
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  21 <refentry id="tmpfiles.d">
  22
  23   <refentryinfo>
  24     <title>tmpfiles.d</title>
  25     <productname>systemd</productname>
  26
  27     <authorgroup>
  28       <author>
  29         <contrib>Documentation</contrib>
  30         <firstname>Brandon</firstname>
  31         <surname>Philips</surname>
  32         <email>brandon@ifup.org</email>
  33       </author>
  34     </authorgroup>
  35   </refentryinfo>
  36
  37   <refmeta>
  38     <refentrytitle>tmpfiles.d</refentrytitle>
  39     <manvolnum>5</manvolnum>
  40   </refmeta>
  41
  42   <refnamediv>
  43     <refname>tmpfiles.d</refname>
  44     <refpurpose>Configuration for creation, deletion and cleaning of
  45     volatile and temporary files</refpurpose>
  46   </refnamediv>
  47
  48   <refsynopsisdiv>
  49     <para><filename>/etc/tmpfiles.d/*.conf</filename></para>
  50     <para><filename>/run/tmpfiles.d/*.conf</filename></para>
  51     <para><filename>/usr/lib/tmpfiles.d/*.conf</filename></para>
  52   </refsynopsisdiv>
  53
  54   <refsect1>
  55     <title>Description</title>
  56
  57     <para><command>systemd-tmpfiles</command> uses the configuration
  58     files from the above directories to describe the creation,
  59     cleaning and removal of volatile and temporary files and
  60     directories which usually reside in directories such as
  61     <filename>/run</filename> or <filename>/tmp</filename>.</para>
  62
  63     <para>Volatile and temporary files and directories are those
  64     located in <filename>/run</filename> (and its alias
  65     <filename>/var/run</filename>), <filename>/tmp</filename>,
  66     <filename>/var/tmp</filename>, the API file systems such as
  67     <filename>/sys</filename> or <filename>/proc</filename>, as well
  68     as some other directories below <filename>/var</filename>.</para>
  69
  70     <para>System daemons frequently require private runtime
  71     directories below <filename>/run</filename> to place communication
  72     sockets and similar in. For these, consider declaring them in
  73     their unit files using <varname>RuntimeDirectory=</varname> (see
  74     <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  75     for details), if this is feasible.</para>
  76   </refsect1>
  77
  78   <refsect1>
  79     <title>Configuration Format</title>
  80
  81     <para>Each configuration file shall be named in the style of
  82     <filename><replaceable>package</replaceable>.conf</filename> or
  83     <filename><replaceable>package</replaceable>-<replaceable>part</replaceable>.conf</filename>.
  84     The second variant should be used when it is desirable to make it
  85     easy to override just this part of configuration.</para>
  86
  87     <para>Files in <filename>/etc/tmpfiles.d</filename> override files
  88     with the same name in <filename>/usr/lib/tmpfiles.d</filename> and
  89     <filename>/run/tmpfiles.d</filename>. Files in
  90     <filename>/run/tmpfiles.d</filename> override files with the same
  91     name in <filename>/usr/lib/tmpfiles.d</filename>. Packages should
  92     install their configuration files in
  93     <filename>/usr/lib/tmpfiles.d</filename>. Files in
  94     <filename>/etc/tmpfiles.d</filename> are reserved for the local
  95     administrator, who may use this logic to override the
  96     configuration files installed by vendor packages. All
  97     configuration files are sorted by their filename in lexicographic
  98     order, regardless of which of the directories they reside in. If
  99     multiple files specify the same path, the entry in the file with
 100     the lexicographically earliest name will be applied.  All other
 101     conflicting entries will be logged as errors. When two lines are
 102     prefix and suffix of each other, then the prefix is always
 103     processed first, the suffix later. Lines that take globs are
 104     applied after those accepting no globs. If multiple operations
 105     shall be applied on the same file, (such as ACL, xattr, file
 106     attribute adjustments), these are always done in the same fixed
 107     order. Otherwise, the files/directories are processed in the order
 108     they are listed.</para>
 109
 110     <para>If the administrator wants to disable a configuration file
 111     supplied by the vendor, the recommended way is to place a symlink
 112     to <filename>/dev/null</filename> in
 113     <filename>/etc/tmpfiles.d/</filename> bearing the same filename.
 114     </para>
 115
 116     <para>The configuration format is one line per path containing
 117     type, path, mode, ownership, age, and argument fields:</para>
 118
 119     <programlisting>#Type Path        Mode UID  GID  Age Argument
 120     d    /run/user   0755 root root 10d -
 121     L    /tmp/foobar -    -    -    -   /dev/null</programlisting>
 122
 123     <para>Fields may be enclosed within quotes and contain C-style escapes.</para>
 124
 125     <refsect2>
 126       <title>Type</title>
 127
 128       <para>The type consists of a single letter and optionally an
 129       exclamation mark.</para>
 130
 131       <para>The following line types are understood:</para>
 132
 133       <variablelist>
 134         <varlistentry>
 135           <term><varname>f</varname></term>
 136           <listitem><para>Create a file if it does not exist yet. If
 137           the argument parameter is given, it will be written to the
 138           file. Does not follow symlinks.</para></listitem>
 139         </varlistentry>
 140
 141         <varlistentry>
 142           <term><varname>F</varname></term>
 143           <listitem><para>Create or truncate a file. If the argument
 144           parameter is given, it will be written to the file. Does not follow symlinks.</para>
 145           </listitem>
 146         </varlistentry>
 147
 148         <varlistentry>
 149           <term><varname>w</varname></term>
 150           <listitem><para>Write the argument parameter to a file, if
 151           the file exists.  Lines of this type accept shell-style
 152           globs in place of normal path names. The argument parameter
 153           will be written without a trailing newline. C-style
 154           backslash escapes are interpreted. Follows
 155           symlinks.</para></listitem>
 156         </varlistentry>
 157
 158         <varlistentry>
 159           <term><varname>d</varname></term>
 160           <listitem><para>Create a directory if it does not exist yet.
 161           </para></listitem>
 162         </varlistentry>
 163
 164         <varlistentry>
 165           <term><varname>D</varname></term>
 166           <listitem><para>Create or empty a directory.</para></listitem>
 167         </varlistentry>
 168
 169         <varlistentry>
 170           <term><varname>v</varname></term>
 171           <listitem><para>Create a subvolume if the path does not
 172           exist yet, the file system supports subvolumes (btrfs), and
 173           the system itself is installed into a subvolume
 174           (specifically: the root directory <filename>/</filename> is
 175           itself a subvolume). Otherwise, create a normal directory, in
 176           the same way as <varname>d</varname>. A subvolume created
 177           with this line type is not assigned to any higher-level
 178           quota group. For that, use <varname>q</varname> or
 179           <varname>Q</varname>, which allow creating simple quota
 180           group hierarchies, see below.</para></listitem>
 181         </varlistentry>
 182
 183         <varlistentry>
 184           <term><varname>q</varname></term>
 185           <listitem><para>Similar to <varname>v</varname>. However,
 186           makes sure that the subvolume will be assigned to the same
 187           higher-level quota groups as the subvolume it has been
 188           created in. This ensures that higher-level limits and
 189           accounting applied to the parent subvolume also include the
 190           specified subvolume. On non-btrfs file systems, this line
 191           type is identical to <varname>d</varname>. If the subvolume
 192           already exists and is already assigned to one or more higher
 193           level quota groups, no change to the quota hierarchy is
 194           made. Also see <varname>Q</varname> below. See <citerefentry
 195           project='die-net'><refentrytitle>btrfs-qgroup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 196           for details about the btrfs quota group
 197           concept.</para></listitem>
 198         </varlistentry>
 199
 200         <varlistentry>
 201           <term><varname>Q</varname></term>
 202           <listitem><para>Similar to <varname>q</varname>. However,
 203           instead of copying the higher-level quota group assignments
 204           from the parent as-is, the lowest quota group of the parent
 205           subvolume is determined that is not the leaf quota
 206           group. Then, an "intermediary" quota group is inserted that
 207           is one level below this level, and shares the same ID part
 208           as the specified subvolume. If no higher-level quota group
 209           exists for the parent subvolume, a new quota group at level
 210           255 sharing the same ID as the specified subvolume is
 211           inserted instead. This new intermediary quota group is then
 212           assigned to the parent subvolume's higher-level quota
 213           groups, and the specified subvolume's leaf quota group is
 214           assigned to it.</para>
 215
 216           <para>Effectively, this has a similar effect as
 217           <varname>q</varname>, however introduces a new higher-level
 218           quota group for the specified subvolume that may be used to
 219           enforce limits and accounting to the specified subvolume and
 220           children subvolume created within it. Thus, by creating
 221           subvolumes only via <varname>q</varname> and
 222           <varname>Q</varname>, a concept of "subtree quotas" is
 223           implemented. Each subvolume for which <varname>Q</varname>
 224           is set will get a "subtree" quota group created, and all
 225           child subvolumes created within it will be assigned to
 226           it. Each subvolume for which <varname>q</varname> is set
 227           will not get such a "subtree" quota group, but it is ensured
 228           that they are added to the same "subtree" quota group as their
 229           immediate parents.</para>
 230
 231           <para>It is recommended to use
 232           <varname>Q</varname> for subvolumes that typically contain
 233           further subvolumes, and where it is desirable to have
 234           accounting and quota limits on all child subvolumes
 235           together. Examples for <varname>Q</varname> are typically
 236           <filename>/home</filename> or
 237           <filename>/var/lib/machines</filename>. In contrast,
 238           <varname>q</varname> should be used for subvolumes that
 239           either usually do not include further subvolumes or where no
 240           accounting and quota limits are needed that apply to all
 241           child subvolumes together. Examples for <varname>q</varname>
 242           are typically <filename>/var</filename> or
 243           <filename>/var/tmp</filename>. As with <varname>Q</varname>,
 244           <varname>q</varname> has no effect on the quota group
 245           hierarchy if the subvolume exists and already has at least
 246           one higher-level quota group assigned.</para></listitem>
 247         </varlistentry>
 248
 249         <varlistentry>
 250           <term><varname>p</varname></term>
 251           <term><varname>p+</varname></term>
 252           <listitem><para>Create a named pipe (FIFO) if it does not
 253           exist yet. If suffixed with <varname>+</varname> and a file
 254           already exists where the pipe is to be created, it will be
 255           removed and be replaced by the pipe.</para></listitem>
 256         </varlistentry>
 257
 258         <varlistentry>
 259           <term><varname>L</varname></term>
 260           <term><varname>L+</varname></term>
 261           <listitem><para>Create a symlink if it does not exist
 262           yet. If suffixed with <varname>+</varname> and a file
 263           already exists where the symlink is to be created, it will
 264           be removed and be replaced by the symlink. If the argument
 265           is omitted, symlinks to files with the same name residing in
 266           the directory <filename>/usr/share/factory/</filename> are
 267           created.</para></listitem>
 268         </varlistentry>
 269
 270         <varlistentry>
 271           <term><varname>c</varname></term>
 272           <term><varname>c+</varname></term>
 273           <listitem><para>Create a character device node if it does
 274           not exist yet. If suffixed with <varname>+</varname> and a
 275           file already exists where the device node is to be created,
 276           it will be removed and be replaced by the device node. It is
 277           recommended to suffix this entry with an exclamation mark to
 278           only create static device nodes at boot, as udev will not
 279           manage static device nodes that are created at runtime.
 280           </para></listitem>
 281         </varlistentry>
 282
 283         <varlistentry>
 284           <term><varname>b</varname></term>
 285           <term><varname>b+</varname></term>
 286           <listitem><para>Create a block device node if it does not
 287           exist yet. If suffixed with <varname>+</varname> and a file
 288           already exists where the device node is to be created, it
 289           will be removed and be replaced by the device node. It is
 290           recommended to suffix this entry with an exclamation mark to
 291           only create static device nodes at boot, as udev will not
 292           manage static device nodes that are created at runtime.
 293           </para></listitem>
 294         </varlistentry>
 295
 296         <varlistentry>
 297           <term><varname>C</varname></term>
 298           <listitem><para>Recursively copy a file or directory, if the
 299           destination files or directories do not exist yet. Note that
 300           this command will not descend into subdirectories if the
 301           destination directory already exists. Instead, the entire
 302           copy operation is skipped. If the argument is omitted, files
 303           from the source directory
 304           <filename>/usr/share/factory/</filename> with the same name
 305           are copied. Does not follow symlinks.</para></listitem>
 306         </varlistentry>
 307
 308         <varlistentry>
 309           <term><varname>x</varname></term>
 310           <listitem><para>Ignore a path during cleaning. Use this type
 311           to exclude paths from clean-up as controlled with the Age
 312           parameter. Note that lines of this type do not influence the
 313           effect of <varname>r</varname> or <varname>R</varname>
 314           lines. Lines of this type accept shell-style globs in place
 315           of normal path names.  </para></listitem>
 316         </varlistentry>
 317
 318         <varlistentry>
 319           <term><varname>X</varname></term>
 320           <listitem><para>Ignore a path during cleaning. Use this type
 321           to exclude paths from clean-up as controlled with the Age
 322           parameter. Unlike <varname>x</varname>, this parameter will
 323           not exclude the content if path is a directory, but only
 324           directory itself. Note that lines of this type do not
 325           influence the effect of <varname>r</varname> or
 326           <varname>R</varname> lines. Lines of this type accept
 327           shell-style globs in place of normal path names.
 328           </para></listitem>
 329         </varlistentry>
 330
 331         <varlistentry>
 332           <term><varname>r</varname></term>
 333           <listitem><para>Remove a file or directory if it exists.
 334           This may not be used to remove non-empty directories, use
 335           <varname>R</varname> for that.  Lines of this type accept
 336           shell-style globs in place of normal path
 337           names. Does not follow symlinks.</para></listitem>
 338         </varlistentry>
 339
 340         <varlistentry>
 341           <term><varname>R</varname></term>
 342           <listitem><para>Recursively remove a path and all its
 343           subdirectories (if it is a directory). Lines of this type
 344           accept shell-style globs in place of normal path
 345           names. Does not follow symlinks.</para></listitem>
 346         </varlistentry>
 347
 348         <varlistentry>
 349           <term><varname>z</varname></term>
 350           <listitem><para>Adjust the access mode, group and user, and
 351           restore the SELinux security context of a file or directory,
 352           if it exists. Lines of this type accept shell-style globs in
 353           place of normal path names. Does not follow symlinks.</para></listitem>
 354         </varlistentry>
 355
 356         <varlistentry>
 357           <term><varname>Z</varname></term>
 358           <listitem><para>Recursively set the access mode, group and
 359           user, and restore the SELinux security context of a file or
 360           directory if it exists, as well as of its subdirectories and
 361           the files contained therein (if applicable). Lines of this
 362           type accept shell-style globs in place of normal path
 363           names. Does not follow symlinks.  </para></listitem>
 364         </varlistentry>
 365
 366         <varlistentry>
 367           <term><varname>t</varname></term>
 368           <listitem><para>Set extended attributes. Lines of this type
 369           accept shell-style globs in place of normal path names.
 370           This can be useful for setting SMACK labels. Does not follow
 371           symlinks.</para></listitem>
 372         </varlistentry>
 373
 374         <varlistentry>
 375           <term><varname>T</varname></term>
 376           <listitem><para>Recursively set extended attributes. Lines
 377           of this type accept shell-style globs in place of normal
 378           path names.  This can be useful for setting SMACK
 379           labels. Does not follow symlinks.  </para></listitem>
 380         </varlistentry>
 381
 382         <varlistentry>
 383           <term><varname>h</varname></term>
 384           <listitem><para>Set file/directory attributes. Lines of this type
 385           accept shell-style globs in place of normal path names.</para>
 386
 387           <para>The format of the argument field is
 388           <varname>[+-=][aAcCdDeijsStTu] </varname>. The prefix
 389           <varname>+</varname> (the default one) causes the
 390           attribute(s) to be added; <varname>-</varname> causes the
 391           attribute(s) to be removed; <varname>=</varname> causes the
 392           attributes to be set exactly as the following letters. The
 393           letters <literal>aAcCdDeijsStTu</literal> select the new
 394           attributes for the files, see
 395           <citerefentry project='man-pages'><refentrytitle>chattr</refentrytitle>
 396           <manvolnum>1</manvolnum></citerefentry> for further information.
 397           </para>
 398           <para>Passing only <varname>=</varname> as argument resets
 399           all the file attributes listed above. It has to be pointed
 400           out that the <varname>=</varname> prefix limits itself to
 401           the attributes corresponding to the letters listed here. All
 402           other attributes will be left untouched. Does not follow
 403           symlinks.</para>
 404           </listitem>
 405         </varlistentry>
 406
 407         <varlistentry>
 408           <term><varname>H</varname></term>
 409           <listitem><para>Recursively set file/directory attributes. Lines
 410           of this type accept shell-style globs in place of normal
 411           path names. Does not follow symlinks.
 412           </para></listitem>
 413         </varlistentry>
 414
 415         <varlistentry>
 416           <term><varname>a</varname></term>
 417           <term><varname>a+</varname></term>
 418           <listitem><para>Set POSIX ACLs (access control lists). If
 419           suffixed with <varname>+</varname>, the specified entries will
 420           be added to the existing set.
 421           <command>systemd-tmpfiles</command> will automatically add
 422           the required base entries for user and group based on the
 423           access mode of the file, unless base entries already exist
 424           or are explicitly specified. The mask will be added if not
 425           specified explicitly or already present. Lines of this type
 426           accept shell-style globs in place of normal path names. This
 427           can be useful for allowing additional access to certain
 428           files. Does not follow symlinks.</para></listitem>
 429         </varlistentry>
 430
 431         <varlistentry>
 432           <term><varname>A</varname></term>
 433           <term><varname>A+</varname></term>
 434           <listitem><para>Same as <varname>a</varname> and
 435           <varname>a+</varname>, but recursive. Does not follow
 436           symlinks.</para></listitem>
 437         </varlistentry>
 438       </variablelist>
 439
 440       <para>If the exclamation mark is used, this line is only safe of
 441       execute during boot, and can break a running system. Lines
 442       without the exclamation mark are presumed to be safe to execute
 443       at any time, e.g. on package upgrades.
 444       <command>systemd-tmpfiles</command> will execute line with an
 445       exclamation mark only if option <option>--boot</option> is
 446       given.</para>
 447
 448       <para>For example:
 449       <programlisting># Make sure these are created by default so that nobody else can
 450       d /tmp/.X11-unix 1777 root root 10d
 451
 452       # Unlink the X11 lock files
 453       r! /tmp/.X[0-9]*-lock</programlisting>
 454       The second line in contrast to the first one would break a
 455       running system, and will only be executed with
 456       <option>--boot</option>.</para>
 457     </refsect2>
 458
 459     <refsect2>
 460       <title>Path</title>
 461
 462       <para>The file system path specification supports simple
 463       specifier expansion. The following expansions are
 464       understood:</para>
 465
 466       <table>
 467         <title>Specifiers available</title>
 468         <tgroup cols='3' align='left' colsep='1' rowsep='1'>
 469           <colspec colname="spec" />
 470           <colspec colname="mean" />
 471           <colspec colname="detail" />
 472           <thead>
 473             <row>
 474               <entry>Specifier</entry>
 475               <entry>Meaning</entry>
 476               <entry>Details</entry>
 477             </row>
 478           </thead>
 479           <tbody>
 480             <row>
 481               <entry><literal>%m</literal></entry>
 482               <entry>Machine ID</entry>
 483               <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>
 484             </row>
 485             <row>
 486               <entry><literal>%b</literal></entry>
 487               <entry>Boot ID</entry>
 488               <entry>The boot ID of the running system, formatted as string. See <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry> for more information.</entry>
 489             </row>
 490             <row>
 491               <entry><literal>%H</literal></entry>
 492               <entry>Host name</entry>
 493               <entry>The hostname of the running system.</entry>
 494             </row>
 495             <row>
 496               <entry><literal>%v</literal></entry>
 497               <entry>Kernel release</entry>
 498               <entry>Identical to <command>uname -r</command> output.</entry>
 499             </row>
 500             <row>
 501               <entry><literal>%%</literal></entry>
 502               <entry>Escaped %</entry>
 503               <entry>Single percent sign.</entry>
 504             </row>
 505           </tbody>
 506         </tgroup>
 507       </table>
 508     </refsect2>
 509
 510     <refsect2>
 511       <title>Mode</title>
 512
 513       <para>The file access mode to use when creating this file or
 514       directory. If omitted or when set to <literal>-</literal>, the
 515       default is used: 0755 for directories, 0644 for all other file
 516       objects.  For <varname>z</varname>, <varname>Z</varname> lines,
 517       if omitted or when set to <literal>-</literal>, the file access
 518       mode will not be modified. This parameter is ignored for
 519       <varname>x</varname>, <varname>r</varname>,
 520       <varname>R</varname>, <varname>L</varname>, <varname>t</varname>,
 521       and <varname>a</varname> lines.</para>
 522
 523       <para>Optionally, if prefixed with <literal>~</literal>, the
 524       access mode is masked based on the already set access bits for
 525       existing file or directories: if the existing file has all
 526       executable bits unset, all executable bits are removed from the
 527       new access mode, too. Similarly, if all read bits are removed
 528       from the old access mode, they will be removed from the new
 529       access mode too, and if all write bits are removed, they will be
 530       removed from the new access mode too. In addition, the
 531       sticky/SUID/SGID bit is removed unless applied to a
 532       directory. This functionality is particularly useful in
 533       conjunction with <varname>Z</varname>.</para>
 534     </refsect2>
 535
 536     <refsect2>
 537       <title>UID, GID</title>
 538
 539       <para>The user and group to use for this file or directory. This
 540       may either be a numeric user/group ID or a user or group
 541       name. If omitted or when set to <literal>-</literal>, the
 542       default 0 (root) is used. For <varname>z</varname> and
 543       <varname>Z</varname> lines, when omitted or when set to
 544       <literal>-</literal>, the file ownership will not be
 545       modified. These parameters are ignored for <varname>x</varname>,
 546       <varname>r</varname>, <varname>R</varname>,
 547       <varname>L</varname>, <varname>t</varname>, and
 548       <varname>a</varname> lines.</para>
 549     </refsect2>
 550
 551     <refsect2>
 552       <title>Age</title>
 553       <para>The date field, when set, is used to decide what files to
 554       delete when cleaning. If a file or directory is older than the
 555       current time minus the age field, it is deleted. The field
 556       format is a series of integers each followed by one of the
 557       following suffixes for the respective time units:
 558       <constant>s</constant>,
 559       <constant>m</constant> or <constant>min</constant>,
 560       <constant>h</constant>,
 561       <constant>d</constant>,
 562       <constant>w</constant>,
 563       <constant>ms</constant>, and
 564       <constant>us</constant>,
 565       meaning seconds, minutes, hours, days, weeks,
 566       milliseconds, and microseconds, respectively. Full names of the time units can
 567       be used too.
 568       </para>
 569
 570       <para>If multiple integers and units are specified, the time
 571       values are summed. If an integer is given without a unit,
 572       <constant>s</constant> is assumed.
 573       </para>
 574
 575       <para>When the age is set to zero, the files are cleaned
 576       unconditionally.</para>
 577
 578       <para>The age field only applies to lines starting with
 579       <varname>d</varname>, <varname>D</varname>,
 580       <varname>v</varname>, <varname>q</varname>,
 581       <varname>Q</varname>, <varname>C</varname>, <varname>x</varname>
 582       and <varname>X</varname>. If omitted or set to
 583       <literal>-</literal>, no automatic clean-up is done.</para>
 584
 585       <para>If the age field starts with a tilde character
 586       <literal>~</literal>, the clean-up is only applied to files and
 587       directories one level inside the directory specified, but not
 588       the files and directories immediately inside it.</para>
 589     </refsect2>
 590
 591     <refsect2>
 592       <title>Argument</title>
 593
 594       <para>For <varname>L</varname> lines determines the destination
 595       path of the symlink. For <varname>c</varname> and
 596       <varname>b</varname>, determines the major/minor of the device
 597       node, with major and minor formatted as integers, separated by
 598       <literal>:</literal>, e.g.  <literal>1:3</literal>. For
 599       <varname>f</varname>, <varname>F</varname>, and
 600       <varname>w</varname>, the argument may be used to specify a short string that
 601       is written to the file, suffixed by a newline. For
 602       <varname>C</varname>, specifies the source file or
 603       directory. For <varname>t</varname> and <varname>T</varname>,
 604       determines extended attributes to be set. For
 605       <varname>a</varname> and <varname>A</varname>, determines ACL
 606       attributes to be set. For <varname>h</varname> and
 607       <varname>H</varname>, determines the file attributes to
 608       set. Ignored for all other lines.</para>
 609     </refsect2>
 610
 611   </refsect1>
 612
 613   <refsect1>
 614     <title>Example</title>
 615     <example>
 616       <title>/etc/tmpfiles.d/screen.conf example</title>
 617       <para><command>screen</command> needs two directories created at
 618       boot with specific modes and ownership.</para>
 619
 620       <programlisting>d /run/screens  1777 root root 10d
 621 d /run/uscreens 0755 root root 10d12h
 622 t /run/screen - - - - user.name="John Smith" security.SMACK64=screen</programlisting>
 623     </example>
 624     <example>
 625       <title>/etc/tmpfiles.d/abrt.conf example</title>
 626       <para><command>abrt</command> needs a directory created at boot with specific mode and ownership and its content should be preserved.</para>
 627
 628       <programlisting>d /var/tmp/abrt 0755 abrt abrt
 629 x /var/tmp/abrt/*</programlisting>
 630     </example>
 631   </refsect1>
 632
 633   <refsect1>
 634     <title>See Also</title>
 635     <para>
 636       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 637       <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 638       <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 639       <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 640       <citerefentry project='man-pages'><refentrytitle>attr</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 641       <citerefentry project='man-pages'><refentrytitle>getfattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 642       <citerefentry project='man-pages'><refentrytitle>setfattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 643       <citerefentry project='man-pages'><refentrytitle>setfacl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 644       <citerefentry project='man-pages'><refentrytitle>getfacl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 645       <citerefentry project='man-pages'><refentrytitle>chattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 646       <citerefentry project='die-net'><refentrytitle>btrfs-subvolume</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 647       <citerefentry project='die-net'><refentrytitle>btrfs-qgroup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 648     </para>
 649   </refsect1>
 650
 651 </refentry>