man/systemd-tmpfiles.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
   5
   6 <refentry id="systemd-tmpfiles"
   7     xmlns:xi="http://www.w3.org/2001/XInclude">
   8
   9   <refentryinfo>
  10     <title>systemd-tmpfiles</title>
  11     <productname>systemd</productname>
  12   </refentryinfo>
  13
  14   <refmeta>
  15     <refentrytitle>systemd-tmpfiles</refentrytitle>
  16     <manvolnum>8</manvolnum>
  17   </refmeta>
  18
  19   <refnamediv>
  20     <refname>systemd-tmpfiles</refname>
  21     <refname>systemd-tmpfiles-setup.service</refname>
  22     <refname>systemd-tmpfiles-setup-dev-early.service</refname>
  23     <refname>systemd-tmpfiles-setup-dev.service</refname>
  24     <refname>systemd-tmpfiles-clean.service</refname>
  25     <refname>systemd-tmpfiles-clean.timer</refname>
  26     <refpurpose>Creates, deletes and cleans up volatile
  27     and temporary files and directories</refpurpose>
  28   </refnamediv>
  29
  30   <refsynopsisdiv>
  31     <cmdsynopsis>
  32       <command>systemd-tmpfiles</command>
  33       <arg choice="opt" rep="repeat">OPTIONS</arg>
  34       <arg choice="opt" rep="repeat"><replaceable>CONFIGFILE</replaceable></arg>
  35     </cmdsynopsis>
  36
  37     <para>System units:
  38 <literallayout><filename>systemd-tmpfiles-setup.service</filename>
  39 <filename>systemd-tmpfiles-setup-dev-early.service</filename>
  40 <filename>systemd-tmpfiles-setup-dev.service</filename>
  41 <filename>systemd-tmpfiles-clean.service</filename>
  42 <filename>systemd-tmpfiles-clean.timer</filename></literallayout></para>
  43
  44     <para>User units:
  45 <literallayout><filename>systemd-tmpfiles-setup.service</filename>
  46 <filename>systemd-tmpfiles-clean.service</filename>
  47 <filename>systemd-tmpfiles-clean.timer</filename></literallayout></para>
  48   </refsynopsisdiv>
  49
  50   <refsect1>
  51     <title>Description</title>
  52
  53     <para><command>systemd-tmpfiles</command> creates, deletes, and cleans up volatile and temporary files
  54     and directories, using the configuration file format and location specified in
  55     <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>. It must
  56     be invoked with one or more options <option>--create</option>, <option>--remove</option>, and
  57     <option>--clean</option>, to select the respective subset of operations.</para>
  58
  59     <para>By default, directives from all configuration files are applied. When invoked with
  60     <option>--replace=<replaceable>PATH</replaceable></option>, arguments specified on the command line are
  61     used instead of the configuration file <replaceable>PATH</replaceable>. Otherwise, if one or more
  62     absolute filenames are passed on the command line, only the directives in these files are applied. If
  63     <literal>-</literal> is specified instead of a filename, directives are read from standard input. If only
  64     the basename of a configuration file is specified, all configuration directories as specified in
  65     <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> are
  66     searched for a matching file and the file found that has the highest priority is executed.</para>
  67
  68     <para>System services (<filename>systemd-tmpfiles-setup.service</filename>,
  69     <filename>systemd-tmpfiles-setup-dev-early.service</filename>,
  70     <filename>systemd-tmpfiles-setup-dev.service</filename>,
  71     <filename>systemd-tmpfiles-clean.service</filename>) invoke <command>systemd-tmpfiles</command> to create
  72     system files and to perform system wide cleanup. Those services read administrator-controlled
  73     configuration files in <filename>tmpfiles.d/</filename> directories. User services
  74     (<filename>systemd-tmpfiles-setup.service</filename>,
  75     <filename>systemd-tmpfiles-clean.service</filename>) also invoke <command>systemd-tmpfiles</command>, but
  76     it reads a separate set of files, which includes user-controlled files under
  77     <filename>~/.config/user-tmpfiles.d/</filename> and <filename>~/.local/share/user-tmpfiles.d/</filename>,
  78     and administrator-controlled files under <filename>/usr/share/user-tmpfiles.d/</filename>. Users may use
  79     this to create and clean up files under their control, but the system instance performs global cleanup
  80     and is not influenced by user configuration. Note that this means a time-based cleanup configured in the
  81     system instance, such as the one typically configured for <filename>/tmp/</filename>, will thus also
  82     affect files created by the user instance if they are placed in <filename>/tmp/</filename>, even if the
  83     user instance's time-based cleanup is turned off.</para>
  84
  85     <para>To re-apply settings after configuration has been modified, simply restart
  86     <filename>systemd-tmpfiles-clean.service</filename>, which will apply any settings which can be safely
  87     executed at runtime. To debug <command>systemd-tmpfiles</command>, it may be useful to invoke it
  88     directly from the command line with increased log level (see <varname>$SYSTEMD_LOG_LEVEL</varname>
  89     below).</para>
  90   </refsect1>
  91
  92   <refsect1>
  93     <title>Options</title>
  94
  95     <para>The following options are understood:</para>
  96
  97     <variablelist>
  98       <varlistentry>
  99         <term><option>--create</option></term>
 100         <listitem><para>If this option is passed, all files and
 101         directories marked with
 102         <varname>f</varname>,
 103         <varname>F</varname>,
 104         <varname>w</varname>,
 105         <varname>d</varname>,
 106         <varname>D</varname>,
 107         <varname>v</varname>,
 108         <varname>p</varname>,
 109         <varname>L</varname>,
 110         <varname>c</varname>,
 111         <varname>b</varname>,
 112         <varname>m</varname>
 113         in the configuration files are created or written to. Files
 114         and directories marked with
 115         <varname>z</varname>,
 116         <varname>Z</varname>,
 117         <varname>t</varname>,
 118         <varname>T</varname>,
 119         <varname>a</varname>, and
 120         <varname>A</varname> have their ownership, access mode and
 121         security labels set.</para></listitem>
 122       </varlistentry>
 123
 124       <varlistentry>
 125         <term><option>--clean</option></term>
 126         <listitem><para>If this option is passed, all files and
 127         directories with an age parameter configured will be cleaned
 128         up.</para></listitem>
 129       </varlistentry>
 130
 131       <varlistentry>
 132         <term><option>--remove</option></term>
 133         <listitem><para>If this option is passed, the contents of
 134         directories marked with <varname>D</varname> or
 135         <varname>R</varname>, and files or directories themselves
 136         marked with <varname>r</varname> or <varname>R</varname> are
 137         removed unless an exclusive or shared BSD lock is taken on them (see <citerefentry
 138         project='man-pages'><refentrytitle>flock</refentrytitle><manvolnum>2</manvolnum></citerefentry>).
 139         </para></listitem>
 140       </varlistentry>
 141
 142       <varlistentry>
 143         <term><option>--user</option></term>
 144         <listitem><para>Execute "user" configuration, i.e. <filename>tmpfiles.d</filename>
 145         files in user configuration directories.</para>
 146
 147         <xi:include href="version-info.xml" xpointer="v236"/></listitem>
 148       </varlistentry>
 149
 150       <varlistentry>
 151         <term><option>--boot</option></term>
 152         <listitem><para>Also execute lines with an exclamation mark. Lines that are not safe to be executed
 153         on a running system may be marked in this way. <command>systemd-tmpfiles</command> is executed in
 154         early boot with <option>--boot</option> specified and will execute those lines. When invoked again
 155         later, it should be called without <option>--boot</option>.</para>
 156
 157         <xi:include href="version-info.xml" xpointer="v209"/></listitem>
 158       </varlistentry>
 159
 160       <varlistentry>
 161         <term><option>--graceful</option></term>
 162         <listitem><para>Ignore configuration lines pertaining to unknown users or groups. This option is
 163         intended to be used in early boot before all users or groups have been created.</para>
 164
 165         <xi:include href="version-info.xml" xpointer="v254"/></listitem>
 166       </varlistentry>
 167
 168       <varlistentry>
 169         <term><option>--prefix=<replaceable>path</replaceable></option></term>
 170         <listitem><para>Only apply rules with paths that start with
 171         the specified prefix. This option can be specified multiple
 172         times.</para>
 173
 174         <xi:include href="version-info.xml" xpointer="v212"/></listitem>
 175       </varlistentry>
 176
 177       <varlistentry>
 178         <term><option>--exclude-prefix=<replaceable>path</replaceable></option></term>
 179         <listitem><para>Ignore rules with paths that start with the
 180         specified prefix. This option can be specified multiple
 181         times.</para>
 182
 183         <xi:include href="version-info.xml" xpointer="v207"/></listitem>
 184       </varlistentry>
 185
 186       <varlistentry>
 187         <term><option>-E</option></term>
 188         <listitem><para>A shortcut for <literal>--exclude-prefix=/dev --exclude-prefix=/proc
 189         --exclude-prefix=/run --exclude-prefix=/sys</literal>, i.e. exclude the hierarchies typically backed
 190         by virtual or memory file systems. This is useful in combination with <option>--root=</option>, if
 191         the specified directory tree contains an OS tree without these virtual/memory file systems mounted
 192         in, as it is typically not desirable to create any files and directories below these subdirectories
 193         if they are supposed to be overmounted during runtime.</para>
 194
 195         <xi:include href="version-info.xml" xpointer="v247"/></listitem>
 196       </varlistentry>
 197
 198       <varlistentry>
 199         <term><option>--root=<replaceable>root</replaceable></option></term>
 200         <listitem><para>Takes a directory path as an argument. All paths will be prefixed with the given alternate
 201         <replaceable>root</replaceable> path, including config search paths.</para>
 202
 203         <para>When this option is used, the libc Name Service Switch (NSS) is bypassed for resolving users
 204         and groups. Instead the files <filename>/etc/passwd</filename> and <filename>/etc/group</filename>
 205         inside the alternate root are read directly. This means that users/groups not listed in these files
 206         will not be resolved, i.e. LDAP NIS and other complex databases are not considered.</para>
 207
 208         <para>Consider combining this with <option>-E</option> to ensure the invocation does not create files
 209         or directories below mount points in the OS image operated on that are typically overmounted during
 210         runtime.</para>
 211
 212         <xi:include href="version-info.xml" xpointer="v212"/></listitem>
 213       </varlistentry>
 214
 215       <varlistentry>
 216         <term><option>--image=<replaceable>image</replaceable></option></term>
 217
 218         <listitem><para>Takes a path to a disk image file or block device node. If specified all operations
 219         are applied to file system in the indicated disk image. This is similar to <option>--root=</option>
 220         but operates on file systems stored in disk images or block devices. The disk image should either
 221         contain just a file system or a set of file systems within a GPT partition table, following the
 222         <ulink url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">Discoverable Partitions
 223         Specification</ulink>. For further information on supported disk images, see
 224         <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
 225         switch of the same name.</para>
 226
 227         <para>Implies <option>-E</option>.</para>
 228
 229         <xi:include href="version-info.xml" xpointer="v247"/></listitem>
 230       </varlistentry>
 231
 232       <xi:include href="standard-options.xml" xpointer="image-policy-open" />
 233
 234       <varlistentry>
 235         <term><option>--replace=<replaceable>PATH</replaceable></option></term>
 236         <listitem><para>When this option is given, one or more positional arguments
 237         must be specified. All configuration files found in the directories listed in
 238         <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 239         will be read, and the configuration given on the command line will be
 240         handled instead of and with the same priority as the configuration file
 241         <replaceable>PATH</replaceable>.</para>
 242
 243         <para>This option is intended to be used when package installation scripts
 244         are running and files belonging to that package are not yet available on
 245         disk, so their contents must be given on the command line, but the admin
 246         configuration might already exist and should be given higher priority.
 247         </para>
 248
 249         <xi:include href="version-info.xml" xpointer="v238"/></listitem>
 250       </varlistentry>
 251
 252       <xi:include href="standard-options.xml" xpointer="cat-config" />
 253       <xi:include href="standard-options.xml" xpointer="no-pager" />
 254       <xi:include href="standard-options.xml" xpointer="help" />
 255       <xi:include href="standard-options.xml" xpointer="version" />
 256     </variablelist>
 257
 258     <para>It is possible to combine <option>--create</option>, <option>--clean</option>, and <option>--remove</option>
 259     in one invocation (in which case removal and cleanup are executed before creation of new files). For example,
 260     during boot the following command line is executed to ensure that all temporary and volatile directories are
 261     removed and created according to the configuration file:</para>
 262
 263     <programlisting>systemd-tmpfiles --remove --create</programlisting>
 264   </refsect1>
 265
 266   <refsect1>
 267     <title>Credentials</title>
 268
 269     <para><command>systemd-tmpfiles</command> supports the service credentials logic as implemented by
 270     <varname>ImportCredential=</varname>/<varname>LoadCredential=</varname>/<varname>SetCredential=</varname>
 271     (see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
 272     details). The following credentials are used when passed in:</para>
 273
 274     <variablelist class='system-credentials'>
 275       <varlistentry>
 276         <term><varname>tmpfiles.extra</varname></term>
 277
 278         <listitem><para> The contents of this credential may contain additional lines to operate on. The
 279         credential contents should follow the same format as any other <filename>tmpfiles.d/</filename>
 280         drop-in configuration file. If this credential is passed it is processed after all of the drop-in
 281         files read from the file system. The lines in the credential can hence augment existing lines of the
 282         OS, but not override them.</para>
 283
 284         <xi:include href="version-info.xml" xpointer="v252"/></listitem>
 285       </varlistentry>
 286     </variablelist>
 287
 288     <para>Note that by default the <filename>systemd-tmpfiles-setup.service</filename> unit file (and related
 289     unit files) is set up to inherit the <literal>tmpfiles.extra</literal> credential from the service
 290     manager.</para>
 291   </refsect1>
 292
 293   <refsect1>
 294     <title>Environment</title>
 295
 296     <variablelist class='environment-variables'>
 297       <xi:include href="common-variables.xml" xpointer="log-level" />
 298       <xi:include href="common-variables.xml" xpointer="log-color" />
 299       <xi:include href="common-variables.xml" xpointer="log-time" />
 300       <xi:include href="common-variables.xml" xpointer="log-location" />
 301       <xi:include href="common-variables.xml" xpointer="log-target" />
 302       <xi:include href="common-variables.xml" xpointer="pager" />
 303       <xi:include href="common-variables.xml" xpointer="less" />
 304       <xi:include href="common-variables.xml" xpointer="lesscharset" />
 305       <xi:include href="common-variables.xml" xpointer="lesssecure" />
 306       <xi:include href="common-variables.xml" xpointer="colors" />
 307       <xi:include href="common-variables.xml" xpointer="urlify" />
 308     </variablelist>
 309   </refsect1>
 310
 311   <refsect1>
 312     <title>Unprivileged --cleanup operation</title>
 313
 314     <para><command>systemd-tmpfiles</command> tries to avoid changing
 315     the access and modification times on the directories it accesses,
 316     which requires <constant>CAP_FOWNER</constant> privileges. When
 317     running as non-root, directories which are checked for files to
 318     clean up will have their access time bumped, which might prevent
 319     their cleanup.
 320     </para>
 321   </refsect1>
 322
 323   <refsect1>
 324     <title>Exit status</title>
 325
 326     <para>On success, 0 is returned. If the configuration was syntactically invalid (syntax errors, missing
 327     arguments, …), so some lines had to be ignored, but no other errors occurred, <constant>65</constant> is
 328     returned (<constant>EX_DATAERR</constant> from <filename>/usr/include/sysexits.h</filename>). If the
 329     configuration was syntactically valid, but could not be executed (lack of permissions, creation of files
 330     in missing directories, invalid contents when writing to <filename>/sys/</filename> values, …),
 331     <constant>73</constant> is returned (<constant>EX_CANTCREAT</constant> from
 332     <filename>/usr/include/sysexits.h</filename>). Otherwise, <constant>1</constant> is returned
 333     (<constant>EXIT_FAILURE</constant> from <filename>/usr/include/stdlib.h</filename>).</para>
 334
 335     <para>Note: when creating items, if the target already exists, but is of the wrong type or otherwise does
 336     not match the requested state, and forced operation has not been requested with <literal>+</literal>,
 337     a message is emitted, but the failure is otherwise ignored.</para>
 338   </refsect1>
 339
 340   <refsect1>
 341     <title>See Also</title>
 342     <para>
 343       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 344       <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 345     </para>
 346   </refsect1>
 347
 348 </refentry>