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 and the file system supports this
 173           (btrfs). Otherwise, create a normal directory, in the same
 174           way as <varname>d</varname>. A subvolume created with this
 175           line type is not assigned to any higher-level quota
 176           group. For that, use <varname>q</varname> or
 177           <varname>Q</varname>, which allow creating simple quota group
 178           hierarchies, see below.</para></listitem>
 179         </varlistentry>
 180
 181         <varlistentry>
 182           <term><varname>q</varname></term>
 183           <listitem><para>Similar to <varname>v</varname>. However,
 184           makes sure that the subvolume will be assigned to the same
 185           higher-level quota groups as the subvolume it has been
 186           created in. This ensures that higher-level limits and
 187           accounting applied to the parent subvolume also include the
 188           specified subvolume. On non-btrfs file systems, this line
 189           type is identical to <varname>d</varname>. If the subvolume
 190           already exists and is already assigned to one or more higher
 191           level quota groups, no change to the quota hierarchy is
 192           made. Also see <varname>Q</varname> below. See <citerefentry
 193           project='die-net'><refentrytitle>btrfs-qgroup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 194           for details about the btrfs quota group
 195           concept.</para></listitem>
 196         </varlistentry>
 197
 198         <varlistentry>
 199           <term><varname>Q</varname></term>
 200           <listitem><para>Similar to <varname>q</varname>. However,
 201           instead of copying the higher-level quota group assignments
 202           from the parent as-is, the lowest quota group of the parent
 203           subvolume is determined that is not the leaf quota
 204           group. Then, an "intermediary" quota group is inserted that
 205           is one level below this level, and shares the same ID part
 206           as the specified subvolume. If no higher-level quota group
 207           exists for the parent subvolume, a new quota group at level
 208           255 sharing the same ID as the specified subvolume is
 209           inserted instead. This new intermediary quota group is then
 210           assigned to the parent subvolume's higher-level quota
 211           groups, and the specified subvolume's leaf quota group is
 212           assigned to it.</para>
 213
 214           <para>Effectively, this has a similar effect as
 215           <varname>q</varname>, however introduces a new higher-level
 216           quota group for the specified subvolume that may be used to
 217           enforce limits and accounting to the specified subvolume and
 218           children subvolume created within it. Thus, by creating
 219           subvolumes only via <varname>q</varname> and
 220           <varname>Q</varname>, a concept of "subtree quotas" is
 221           implemented. Each subvolume for which <varname>Q</varname>
 222           is set will get a "subtree" quota group created, and all
 223           child subvolumes created within it will be assigned to
 224           it. Each subvolume for which <varname>q</varname> is set
 225           will not get such a "subtree" quota group, but it is ensured
 226           that they are added to the same "subtree" quota group as their
 227           immediate parents.</para>
 228
 229           <para>It is recommended to use
 230           <varname>Q</varname> for subvolumes that typically contain
 231           further subvolumes, and where it is desirable to have
 232           accounting and quota limits on all child subvolumes
 233           together. Examples for <varname>Q</varname> are typically
 234           <filename>/home</filename> or
 235           <filename>/var/lib/machines</filename>. In contrast,
 236           <varname>q</varname> should be used for subvolumes that
 237           either usually do not include further subvolumes or where no
 238           accounting and quota limits are needed that apply to all
 239           child subvolumes together. Examples for <varname>q</varname>
 240           are typically <filename>/var</filename> or
 241           <filename>/var/tmp</filename>. As with <varname>Q</varname>,
 242           <varname>q</varname> has no effect on the quota group
 243           hierarchy if the subvolume exists and already has at least
 244           one higher-level quota group assigned.</para></listitem>
 245         </varlistentry>
 246
 247         <varlistentry>
 248           <term><varname>p</varname></term>
 249           <term><varname>p+</varname></term>
 250           <listitem><para>Create a named pipe (FIFO) if it does not
 251           exist yet. If suffixed with <varname>+</varname> and a file
 252           already exists where the pipe is to be created, it will be
 253           removed and be replaced by the pipe.</para></listitem>
 254         </varlistentry>
 255
 256         <varlistentry>
 257           <term><varname>L</varname></term>
 258           <term><varname>L+</varname></term>
 259           <listitem><para>Create a symlink if it does not exist
 260           yet. If suffixed with <varname>+</varname> and a file
 261           already exists where the symlink is to be created, it will
 262           be removed and be replaced by the symlink. If the argument
 263           is omitted, symlinks to files with the same name residing in
 264           the directory <filename>/usr/share/factory/</filename> are
 265           created.</para></listitem>
 266         </varlistentry>
 267
 268         <varlistentry>
 269           <term><varname>c</varname></term>
 270           <term><varname>c+</varname></term>
 271           <listitem><para>Create a character device node if it does
 272           not exist yet. If suffixed with <varname>+</varname> and a
 273           file already exists where the device node is to be created,
 274           it will be removed and be replaced by the device node. It is
 275           recommended to suffix this entry with an exclamation mark to
 276           only create static device nodes at boot, as udev will not
 277           manage static device nodes that are created at runtime.
 278           </para></listitem>
 279         </varlistentry>
 280
 281         <varlistentry>
 282           <term><varname>b</varname></term>
 283           <term><varname>b+</varname></term>
 284           <listitem><para>Create a block device node if it does not
 285           exist yet. If suffixed with <varname>+</varname> and a file
 286           already exists where the device node is to be created, it
 287           will be removed and be replaced by the device node. It is
 288           recommended to suffix this entry with an exclamation mark to
 289           only create static device nodes at boot, as udev will not
 290           manage static device nodes that are created at runtime.
 291           </para></listitem>
 292         </varlistentry>
 293
 294         <varlistentry>
 295           <term><varname>C</varname></term>
 296           <listitem><para>Recursively copy a file or directory, if the
 297           destination files or directories do not exist yet. Note that
 298           this command will not descend into subdirectories if the
 299           destination directory already exists. Instead, the entire
 300           copy operation is skipped. If the argument is omitted, files
 301           from the source directory
 302           <filename>/usr/share/factory/</filename> with the same name
 303           are copied. Does not follow symlinks.</para></listitem>
 304         </varlistentry>
 305
 306         <varlistentry>
 307           <term><varname>x</varname></term>
 308           <listitem><para>Ignore a path during cleaning. Use this type
 309           to exclude paths from clean-up as controlled with the Age
 310           parameter. Note that lines of this type do not influence the
 311           effect of <varname>r</varname> or <varname>R</varname>
 312           lines. Lines of this type accept shell-style globs in place
 313           of normal path names.  </para></listitem>
 314         </varlistentry>
 315
 316         <varlistentry>
 317           <term><varname>X</varname></term>
 318           <listitem><para>Ignore a path during cleaning. Use this type
 319           to exclude paths from clean-up as controlled with the Age
 320           parameter. Unlike <varname>x</varname>, this parameter will
 321           not exclude the content if path is a directory, but only
 322           directory itself. Note that lines of this type do not
 323           influence the effect of <varname>r</varname> or
 324           <varname>R</varname> lines. Lines of this type accept
 325           shell-style globs in place of normal path names.
 326           </para></listitem>
 327         </varlistentry>
 328
 329         <varlistentry>
 330           <term><varname>r</varname></term>
 331           <listitem><para>Remove a file or directory if it exists.
 332           This may not be used to remove non-empty directories, use
 333           <varname>R</varname> for that.  Lines of this type accept
 334           shell-style globs in place of normal path
 335           names. Does not follow symlinks.</para></listitem>
 336         </varlistentry>
 337
 338         <varlistentry>
 339           <term><varname>R</varname></term>
 340           <listitem><para>Recursively remove a path and all its
 341           subdirectories (if it is a directory). Lines of this type
 342           accept shell-style globs in place of normal path
 343           names. Does not follow symlinks.</para></listitem>
 344         </varlistentry>
 345
 346         <varlistentry>
 347           <term><varname>z</varname></term>
 348           <listitem><para>Adjust the access mode, group and user, and
 349           restore the SELinux security context of a file or directory,
 350           if it exists. Lines of this type accept shell-style globs in
 351           place of normal path names. Does not follow symlinks.</para></listitem>
 352         </varlistentry>
 353
 354         <varlistentry>
 355           <term><varname>Z</varname></term>
 356           <listitem><para>Recursively set the access mode, group and
 357           user, and restore the SELinux security context of a file or
 358           directory if it exists, as well as of its subdirectories and
 359           the files contained therein (if applicable). Lines of this
 360           type accept shell-style globs in place of normal path
 361           names. Does not follow symlinks.  </para></listitem>
 362         </varlistentry>
 363
 364         <varlistentry>
 365           <term><varname>t</varname></term>
 366           <listitem><para>Set extended attributes. Lines of this type
 367           accept shell-style globs in place of normal path names.
 368           This can be useful for setting SMACK labels. Does not follow
 369           symlinks.</para></listitem>
 370         </varlistentry>
 371
 372         <varlistentry>
 373           <term><varname>T</varname></term>
 374           <listitem><para>Recursively set extended attributes. Lines
 375           of this type accept shell-style globs in place of normal
 376           path names.  This can be useful for setting SMACK
 377           labels. Does not follow symlinks.  </para></listitem>
 378         </varlistentry>
 379
 380         <varlistentry>
 381           <term><varname>h</varname></term>
 382           <listitem><para>Set file/directory attributes. Lines of this type
 383           accept shell-style globs in place of normal path names.</para>
 384
 385           <para>The format of the argument field is
 386           <varname>[+-=][aAcCdDeijsStTu] </varname>. The prefix
 387           <varname>+</varname> (the default one) causes the
 388           attribute(s) to be added; <varname>-</varname> causes the
 389           attribute(s) to be removed; <varname>=</varname> causes the
 390           attributes to be set exactly as the following letters. The
 391           letters <literal>aAcCdDeijsStTu</literal> select the new
 392           attributes for the files, see
 393           <citerefentry project='man-pages'><refentrytitle>chattr</refentrytitle>
 394           <manvolnum>1</manvolnum></citerefentry> for further information.
 395           </para>
 396           <para>Passing only <varname>=</varname> as argument resets
 397           all the file attributes listed above. It has to be pointed
 398           out that the <varname>=</varname> prefix limits itself to
 399           the attributes corresponding to the letters listed here. All
 400           other attributes will be left untouched. Does not follow
 401           symlinks.</para>
 402           </listitem>
 403         </varlistentry>
 404
 405         <varlistentry>
 406           <term><varname>H</varname></term>
 407           <listitem><para>Recursively set file/directory attributes. Lines
 408           of this type accept shell-style globs in place of normal
 409           path names. Does not follow symlinks.
 410           </para></listitem>
 411         </varlistentry>
 412
 413         <varlistentry>
 414           <term><varname>a</varname></term>
 415           <term><varname>a+</varname></term>
 416           <listitem><para>Set POSIX ACLs (access control lists). If
 417           suffixed with <varname>+</varname>, the specified entries will
 418           be added to the existing set.
 419           <command>systemd-tmpfiles</command> will automatically add
 420           the required base entries for user and group based on the
 421           access mode of the file, unless base entries already exist
 422           or are explictly specified. The mask will be added if not
 423           specified explicitly or already present. Lines of this type
 424           accept shell-style globs in place of normal path names. This
 425           can be useful for allowing additional access to certain
 426           files. Does not follow symlinks.</para></listitem>
 427         </varlistentry>
 428
 429         <varlistentry>
 430           <term><varname>A</varname></term>
 431           <term><varname>A+</varname></term>
 432           <listitem><para>Same as <varname>a</varname> and
 433           <varname>a+</varname>, but recursive. Does not follow
 434           symlinks.</para></listitem>
 435         </varlistentry>
 436       </variablelist>
 437
 438       <para>If the exclamation mark is used, this line is only safe of
 439       execute during boot, and can break a running system. Lines
 440       without the exclamation mark are presumed to be safe to execute
 441       at any time, e.g. on package upgrades.
 442       <command>systemd-tmpfiles</command> will execute line with an
 443       exclamation mark only if option <option>--boot</option> is
 444       given.</para>
 445
 446       <para>For example:
 447       <programlisting># Make sure these are created by default so that nobody else can
 448       d /tmp/.X11-unix 1777 root root 10d
 449
 450       # Unlink the X11 lock files
 451       r! /tmp/.X[0-9]*-lock</programlisting>
 452       The second line in contrast to the first one would break a
 453       running system, and will only be executed with
 454       <option>--boot</option>.</para>
 455     </refsect2>
 456
 457     <refsect2>
 458       <title>Path</title>
 459
 460       <para>The file system path specification supports simple
 461       specifier expansion. The following expansions are
 462       understood:</para>
 463
 464       <table>
 465         <title>Specifiers available</title>
 466         <tgroup cols='3' align='left' colsep='1' rowsep='1'>
 467           <colspec colname="spec" />
 468           <colspec colname="mean" />
 469           <colspec colname="detail" />
 470           <thead>
 471             <row>
 472               <entry>Specifier</entry>
 473               <entry>Meaning</entry>
 474               <entry>Details</entry>
 475             </row>
 476           </thead>
 477           <tbody>
 478             <row>
 479               <entry><literal>%m</literal></entry>
 480               <entry>Machine ID</entry>
 481               <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>
 482             </row>
 483             <row>
 484               <entry><literal>%b</literal></entry>
 485               <entry>Boot ID</entry>
 486               <entry>The boot ID of the running system, formatted as string. See <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry> for more information.</entry>
 487             </row>
 488             <row>
 489               <entry><literal>%H</literal></entry>
 490               <entry>Host name</entry>
 491               <entry>The hostname of the running system.</entry>
 492             </row>
 493             <row>
 494               <entry><literal>%v</literal></entry>
 495               <entry>Kernel release</entry>
 496               <entry>Identical to <command>uname -r</command> output.</entry>
 497             </row>
 498             <row>
 499               <entry><literal>%%</literal></entry>
 500               <entry>Escaped %</entry>
 501               <entry>Single percent sign.</entry>
 502             </row>
 503           </tbody>
 504         </tgroup>
 505       </table>
 506     </refsect2>
 507
 508     <refsect2>
 509       <title>Mode</title>
 510
 511       <para>The file access mode to use when creating this file or
 512       directory. If omitted or when set to <literal>-</literal>, the
 513       default is used: 0755 for directories, 0644 for all other file
 514       objects.  For <varname>z</varname>, <varname>Z</varname> lines,
 515       if omitted or when set to <literal>-</literal>, the file access
 516       mode will not be modified. This parameter is ignored for
 517       <varname>x</varname>, <varname>r</varname>,
 518       <varname>R</varname>, <varname>L</varname>, <varname>t</varname>,
 519       and <varname>a</varname> lines.</para>
 520
 521       <para>Optionally, if prefixed with <literal>~</literal>, the
 522       access mode is masked based on the already set access bits for
 523       existing file or directories: if the existing file has all
 524       executable bits unset, all executable bits are removed from the
 525       new access mode, too. Similarly, if all read bits are removed
 526       from the old access mode, they will be removed from the new
 527       access mode too, and if all write bits are removed, they will be
 528       removed from the new access mode too. In addition, the
 529       sticky/SUID/SGID bit is removed unless applied to a
 530       directory. This functionality is particularly useful in
 531       conjunction with <varname>Z</varname>.</para>
 532     </refsect2>
 533
 534     <refsect2>
 535       <title>UID, GID</title>
 536
 537       <para>The user and group to use for this file or directory. This
 538       may either be a numeric user/group ID or a user or group
 539       name. If omitted or when set to <literal>-</literal>, the
 540       default 0 (root) is used. For <varname>z</varname> and
 541       <varname>Z</varname> lines, when omitted or when set to
 542       <literal>-</literal>, the file ownership will not be
 543       modified. These parameters are ignored for <varname>x</varname>,
 544       <varname>r</varname>, <varname>R</varname>,
 545       <varname>L</varname>, <varname>t</varname>, and
 546       <varname>a</varname> lines.</para>
 547     </refsect2>
 548
 549     <refsect2>
 550       <title>Age</title>
 551       <para>The date field, when set, is used to decide what files to
 552       delete when cleaning. If a file or directory is older than the
 553       current time minus the age field, it is deleted. The field
 554       format is a series of integers each followed by one of the
 555       following suffixes for the respective time units:
 556       <constant>s</constant>,
 557       <constant>m</constant> or <constant>min</constant>,
 558       <constant>h</constant>,
 559       <constant>d</constant>,
 560       <constant>w</constant>,
 561       <constant>ms</constant>, and
 562       <constant>us</constant>,
 563       meaning seconds, minutes, hours, days, weeks,
 564       milliseconds, and microseconds, respectively. Full names of the time units can
 565       be used too.
 566       </para>
 567
 568       <para>If multiple integers and units are specified, the time
 569       values are summed. If an integer is given without a unit,
 570       <constant>s</constant> is assumed.
 571       </para>
 572
 573       <para>When the age is set to zero, the files are cleaned
 574       unconditionally.</para>
 575
 576       <para>The age field only applies to lines starting with
 577       <varname>d</varname>, <varname>D</varname>,
 578       <varname>v</varname>, <varname>q</varname>,
 579       <varname>Q</varname>, <varname>C</varname>, <varname>x</varname>
 580       and <varname>X</varname>. If omitted or set to
 581       <literal>-</literal>, no automatic clean-up is done.</para>
 582
 583       <para>If the age field starts with a tilde character
 584       <literal>~</literal>, the clean-up is only applied to files and
 585       directories one level inside the directory specified, but not
 586       the files and directories immediately inside it.</para>
 587     </refsect2>
 588
 589     <refsect2>
 590       <title>Argument</title>
 591
 592       <para>For <varname>L</varname> lines determines the destination
 593       path of the symlink. For <varname>c</varname> and
 594       <varname>b</varname>, determines the major/minor of the device
 595       node, with major and minor formatted as integers, separated by
 596       <literal>:</literal>, e.g.  <literal>1:3</literal>. For
 597       <varname>f</varname>, <varname>F</varname>, and
 598       <varname>w</varname>, the argument may be used to specify a short string that
 599       is written to the file, suffixed by a newline. For
 600       <varname>C</varname>, specifies the source file or
 601       directory. For <varname>t</varname> and <varname>T</varname>,
 602       determines extended attributes to be set. For
 603       <varname>a</varname> and <varname>A</varname>, determines ACL
 604       attributes to be set. For <varname>h</varname> and
 605       <varname>H</varname>, determines the file attributes to
 606       set. Ignored for all other lines.</para>
 607     </refsect2>
 608
 609   </refsect1>
 610
 611   <refsect1>
 612     <title>Example</title>
 613     <example>
 614       <title>/etc/tmpfiles.d/screen.conf example</title>
 615       <para><command>screen</command> needs two directories created at
 616       boot with specific modes and ownership.</para>
 617
 618       <programlisting>d /run/screens  1777 root root 10d
 619 d /run/uscreens 0755 root root 10d12h
 620 t /run/screen - - - - user.name="John Smith" security.SMACK64=screen</programlisting>
 621     </example>
 622     <example>
 623       <title>/etc/tmpfiles.d/abrt.conf example</title>
 624       <para><command>abrt</command> needs a directory created at boot with specific mode and ownership and its content should be preserved.</para>
 625
 626       <programlisting>d /var/tmp/abrt 0755 abrt abrt
 627 x /var/tmp/abrt/*</programlisting>
 628     </example>
 629   </refsect1>
 630
 631   <refsect1>
 632     <title>See Also</title>
 633     <para>
 634       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 635       <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 636       <citerefentry><refentrytitle>systemd-delta</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 637       <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 638       <citerefentry project='man-pages'><refentrytitle>attr</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 639       <citerefentry project='man-pages'><refentrytitle>getfattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 640       <citerefentry project='man-pages'><refentrytitle>setfattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 641       <citerefentry project='man-pages'><refentrytitle>setfacl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 642       <citerefentry project='man-pages'><refentrytitle>getfacl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 643       <citerefentry project='man-pages'><refentrytitle>chattr</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 644       <citerefentry project='die-net'><refentrytitle>btrfs-subvolume</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 645       <citerefentry project='die-net'><refentrytitle>btrfs-qgroup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 646     </para>
 647   </refsect1>
 648
 649 </refentry>