man/systemd-tmpfiles.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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   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     <simplelist>
  39       <member><filename>systemd-tmpfiles-setup.service</filename></member>
  40       <member><filename>systemd-tmpfiles-setup-dev-early.service</filename></member>
  41       <member><filename>systemd-tmpfiles-setup-dev.service</filename></member>
  42       <member><filename>systemd-tmpfiles-clean.service</filename></member>
  43       <member><filename>systemd-tmpfiles-clean.timer</filename></member>
  44     </simplelist>
  45     </para>
  46
  47     <para>User units:
  48     <simplelist>
  49       <member><filename>systemd-tmpfiles-setup.service</filename></member>
  50       <member><filename>systemd-tmpfiles-clean.service</filename></member>
  51       <member><filename>systemd-tmpfiles-clean.timer</filename></member>
  52     </simplelist>
  53     </para>
  54   </refsynopsisdiv>
  55
  56   <refsect1>
  57     <title>Description</title>
  58
  59     <para><command>systemd-tmpfiles</command> creates, deletes, and cleans up volatile and temporary files
  60     and directories, using the configuration file format and location specified in
  61     <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>. It must
  62     be invoked with one or more options <option>--create</option>, <option>--remove</option>, and
  63     <option>--clean</option>, to select the respective subset of operations.</para>
  64
  65     <para>By default, directives from all configuration files are applied. When invoked with
  66     <option>--replace=<replaceable>PATH</replaceable></option>, arguments specified on the command line are
  67     used instead of the configuration file <replaceable>PATH</replaceable>. Otherwise, if one or more
  68     absolute filenames are passed on the command line, only the directives in these files are applied. If
  69     <literal>-</literal> is specified instead of a filename, directives are read from standard input. If only
  70     the basename of a configuration file is specified, all configuration directories as specified in
  71     <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> are
  72     searched for a matching file and the file found that has the highest priority is executed.</para>
  73
  74     <para>System services (<filename>systemd-tmpfiles-setup.service</filename>,
  75     <filename>systemd-tmpfiles-setup-dev-early.service</filename>,
  76     <filename>systemd-tmpfiles-setup-dev.service</filename>,
  77     <filename>systemd-tmpfiles-clean.service</filename>) invoke <command>systemd-tmpfiles</command> to create
  78     system files and to perform system wide cleanup. Those services read administrator-controlled
  79     configuration files in <filename>tmpfiles.d/</filename> directories. User services
  80     (<filename>systemd-tmpfiles-setup.service</filename>,
  81     <filename>systemd-tmpfiles-clean.service</filename>) also invoke <command>systemd-tmpfiles</command>, but
  82     it reads a separate set of files, which includes user-controlled files under
  83     <filename>~/.config/user-tmpfiles.d/</filename> and <filename>~/.local/share/user-tmpfiles.d/</filename>,
  84     and administrator-controlled files under <filename>/usr/share/user-tmpfiles.d/</filename>. Users may use
  85     this to create and clean up files under their control, but the system instance performs global cleanup
  86     and is not influenced by user configuration. Note that this means a time-based cleanup configured in the
  87     system instance, such as the one typically configured for <filename>/tmp/</filename>, will thus also
  88     affect files created by the user instance if they are placed in <filename>/tmp/</filename>, even if the
  89     user instance's time-based cleanup is turned off.</para>
  90
  91     <para>To re-apply settings after configuration has been modified, simply restart
  92     <filename>systemd-tmpfiles-clean.service</filename>, which will apply any settings which can be safely
  93     executed at runtime. To debug <command>systemd-tmpfiles</command>, it may be useful to invoke it
  94     directly from the command line with increased log level (see <varname>$SYSTEMD_LOG_LEVEL</varname>
  95     below).</para>
  96   </refsect1>
  97
  98   <refsect1>
  99     <title>Options</title>
 100
 101     <para>The following options are understood:</para>
 102
 103     <variablelist>
 104       <varlistentry>
 105         <term><option>--create</option></term>
 106         <listitem><para>If this option is passed, all files and
 107         directories marked with
 108         <varname>f</varname>,
 109         <varname>F</varname>,
 110         <varname>w</varname>,
 111         <varname>d</varname>,
 112         <varname>D</varname>,
 113         <varname>v</varname>,
 114         <varname>p</varname>,
 115         <varname>L</varname>,
 116         <varname>c</varname>,
 117         <varname>b</varname>,
 118         <varname>m</varname>
 119         in the configuration files are created or written to. Files
 120         and directories marked with
 121         <varname>z</varname>,
 122         <varname>Z</varname>,
 123         <varname>t</varname>,
 124         <varname>T</varname>,
 125         <varname>a</varname>, and
 126         <varname>A</varname> have their ownership, access mode and
 127         security labels set.</para></listitem>
 128       </varlistentry>
 129
 130       <varlistentry>
 131         <term><option>--clean</option></term>
 132         <listitem><para>If this option is passed, all files and
 133         directories with an age parameter configured will be cleaned
 134         up.</para></listitem>
 135       </varlistentry>
 136
 137       <varlistentry>
 138         <term><option>--remove</option></term>
 139         <listitem><para>If this option is passed, the contents of
 140         directories marked with <varname>D</varname> or
 141         <varname>R</varname>, and files or directories themselves
 142         marked with <varname>r</varname> or <varname>R</varname> are
 143         removed unless an exclusive or shared BSD lock is taken on them (see <citerefentry
 144         project='man-pages'><refentrytitle>flock</refentrytitle><manvolnum>2</manvolnum></citerefentry>).
 145         </para></listitem>
 146       </varlistentry>
 147
 148       <varlistentry>
 149         <term><option>--user</option></term>
 150         <listitem><para>Execute "user" configuration, i.e. <filename>tmpfiles.d</filename>
 151         files in user configuration directories.</para>
 152
 153         <xi:include href="version-info.xml" xpointer="v236"/></listitem>
 154       </varlistentry>
 155
 156       <varlistentry>
 157         <term><option>--boot</option></term>
 158         <listitem><para>Also execute lines with an exclamation mark. Lines that are not safe to be executed
 159         on a running system may be marked in this way. <command>systemd-tmpfiles</command> is executed in
 160         early boot with <option>--boot</option> specified and will execute those lines. When invoked again
 161         later, it should be called without <option>--boot</option>.</para>
 162
 163         <xi:include href="version-info.xml" xpointer="v209"/></listitem>
 164       </varlistentry>
 165
 166       <varlistentry>
 167         <term><option>--graceful</option></term>
 168         <listitem><para>Ignore configuration lines pertaining to unknown users or groups. This option is
 169         intended to be used in early boot before all users or groups have been created.</para>
 170
 171         <xi:include href="version-info.xml" xpointer="v254"/></listitem>
 172       </varlistentry>
 173
 174       <varlistentry>
 175         <term><option>--prefix=<replaceable>path</replaceable></option></term>
 176         <listitem><para>Only apply rules with paths that start with
 177         the specified prefix. This option can be specified multiple
 178         times.</para>
 179
 180         <xi:include href="version-info.xml" xpointer="v212"/></listitem>
 181       </varlistentry>
 182
 183       <varlistentry>
 184         <term><option>--exclude-prefix=<replaceable>path</replaceable></option></term>
 185         <listitem><para>Ignore rules with paths that start with the
 186         specified prefix. This option can be specified multiple
 187         times.</para>
 188
 189         <xi:include href="version-info.xml" xpointer="v207"/></listitem>
 190       </varlistentry>
 191
 192       <varlistentry>
 193         <term><option>-E</option></term>
 194         <listitem><para>A shortcut for <literal>--exclude-prefix=/dev --exclude-prefix=/proc
 195         --exclude-prefix=/run --exclude-prefix=/sys</literal>, i.e. exclude the hierarchies typically backed
 196         by virtual or memory file systems. This is useful in combination with <option>--root=</option>, if
 197         the specified directory tree contains an OS tree without these virtual/memory file systems mounted
 198         in, as it is typically not desirable to create any files and directories below these subdirectories
 199         if they are supposed to be overmounted during runtime.</para>
 200
 201         <xi:include href="version-info.xml" xpointer="v247"/></listitem>
 202       </varlistentry>
 203
 204       <varlistentry>
 205         <term><option>--root=<replaceable>root</replaceable></option></term>
 206         <listitem><para>Takes a directory path as an argument. All paths will be prefixed with the given alternate
 207         <replaceable>root</replaceable> path, including config search paths.</para>
 208
 209         <para>When this option is used, the libc Name Service Switch (NSS) is bypassed for resolving users
 210         and groups. Instead the files <filename>/etc/passwd</filename> and <filename>/etc/group</filename>
 211         inside the alternate root are read directly. This means that users/groups not listed in these files
 212         will not be resolved, i.e. LDAP NIS and other complex databases are not considered.</para>
 213
 214         <para>Consider combining this with <option>-E</option> to ensure the invocation does not create files
 215         or directories below mount points in the OS image operated on that are typically overmounted during
 216         runtime.</para>
 217
 218         <xi:include href="version-info.xml" xpointer="v212"/></listitem>
 219       </varlistentry>
 220
 221       <varlistentry>
 222         <term><option>--image=<replaceable>image</replaceable></option></term>
 223
 224         <listitem><para>Takes a path to a disk image file or block device node. If specified all operations
 225         are applied to file system in the indicated disk image. This is similar to <option>--root=</option>
 226         but operates on file systems stored in disk images or block devices. The disk image should either
 227         contain just a file system or a set of file systems within a GPT partition table, following the
 228         <ulink url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">Discoverable Partitions
 229         Specification</ulink>. For further information on supported disk images, see
 230         <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
 231         switch of the same name.</para>
 232
 233         <para>Implies <option>-E</option>.</para>
 234
 235         <xi:include href="version-info.xml" xpointer="v247"/></listitem>
 236       </varlistentry>
 237
 238       <xi:include href="standard-options.xml" xpointer="image-policy-open" />
 239
 240       <varlistentry>
 241         <term><option>--replace=<replaceable>PATH</replaceable></option></term>
 242         <listitem><para>When this option is given, one or more positional arguments
 243         must be specified. All configuration files found in the directories listed in
 244         <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 245         will be read, and the configuration given on the command line will be
 246         handled instead of and with the same priority as the configuration file
 247         <replaceable>PATH</replaceable>.</para>
 248
 249         <para>This option is intended to be used when package installation scripts
 250         are running and files belonging to that package are not yet available on
 251         disk, so their contents must be given on the command line, but the admin
 252         configuration might already exist and should be given higher priority.
 253         </para>
 254
 255         <xi:include href="version-info.xml" xpointer="v238"/></listitem>
 256       </varlistentry>
 257
 258       <xi:include href="standard-options.xml" xpointer="cat-config" />
 259       <xi:include href="standard-options.xml" xpointer="tldr" />
 260       <xi:include href="standard-options.xml" xpointer="no-pager" />
 261       <xi:include href="standard-options.xml" xpointer="help" />
 262       <xi:include href="standard-options.xml" xpointer="version" />
 263     </variablelist>
 264
 265     <para>It is possible to combine <option>--create</option>, <option>--clean</option>, and <option>--remove</option>
 266     in one invocation (in which case removal and cleanup are executed before creation of new files). For example,
 267     during boot the following command line is executed to ensure that all temporary and volatile directories are
 268     removed and created according to the configuration file:</para>
 269
 270     <programlisting>systemd-tmpfiles --remove --create</programlisting>
 271   </refsect1>
 272
 273   <refsect1>
 274     <title>Credentials</title>
 275
 276     <para><command>systemd-tmpfiles</command> supports the service credentials logic as implemented by
 277     <varname>ImportCredential=</varname>/<varname>LoadCredential=</varname>/<varname>SetCredential=</varname>
 278     (see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
 279     details). The following credentials are used when passed in:</para>
 280
 281     <variablelist class='system-credentials'>
 282       <varlistentry>
 283         <term><varname>tmpfiles.extra</varname></term>
 284
 285         <listitem><para> The contents of this credential may contain additional lines to operate on. The
 286         credential contents should follow the same format as any other <filename>tmpfiles.d/</filename>
 287         drop-in configuration file. If this credential is passed it is processed after all of the drop-in
 288         files read from the file system. The lines in the credential can hence augment existing lines of the
 289         OS, but not override them.</para>
 290
 291         <xi:include href="version-info.xml" xpointer="v252"/></listitem>
 292       </varlistentry>
 293     </variablelist>
 294
 295     <para>Note that by default the <filename>systemd-tmpfiles-setup.service</filename> unit file (and related
 296     unit files) is set up to inherit the <literal>tmpfiles.extra</literal> credential from the service
 297     manager.</para>
 298   </refsect1>
 299
 300   <refsect1>
 301     <title>Environment</title>
 302
 303     <variablelist class='environment-variables'>
 304       <xi:include href="common-variables.xml" xpointer="log-level" />
 305       <xi:include href="common-variables.xml" xpointer="log-color" />
 306       <xi:include href="common-variables.xml" xpointer="log-time" />
 307       <xi:include href="common-variables.xml" xpointer="log-location" />
 308       <xi:include href="common-variables.xml" xpointer="log-target" />
 309       <xi:include href="common-variables.xml" xpointer="pager" />
 310       <xi:include href="common-variables.xml" xpointer="less" />
 311       <xi:include href="common-variables.xml" xpointer="lesscharset" />
 312       <xi:include href="common-variables.xml" xpointer="lesssecure" />
 313       <xi:include href="common-variables.xml" xpointer="colors" />
 314       <xi:include href="common-variables.xml" xpointer="urlify" />
 315     </variablelist>
 316   </refsect1>
 317
 318   <refsect1>
 319     <title>Unprivileged --cleanup operation</title>
 320
 321     <para><command>systemd-tmpfiles</command> tries to avoid changing
 322     the access and modification times on the directories it accesses,
 323     which requires <constant>CAP_FOWNER</constant> privileges. When
 324     running as non-root, directories which are checked for files to
 325     clean up will have their access time bumped, which might prevent
 326     their cleanup.
 327     </para>
 328   </refsect1>
 329
 330   <refsect1>
 331     <title>Exit status</title>
 332
 333     <para>On success, 0 is returned. If the configuration was syntactically invalid (syntax errors, missing
 334     arguments, …), so some lines had to be ignored, but no other errors occurred, <constant>65</constant> is
 335     returned (<constant>EX_DATAERR</constant> from <filename>/usr/include/sysexits.h</filename>). If the
 336     configuration was syntactically valid, but could not be executed (lack of permissions, creation of files
 337     in missing directories, invalid contents when writing to <filename>/sys/</filename> values, …),
 338     <constant>73</constant> is returned (<constant>EX_CANTCREAT</constant> from
 339     <filename>/usr/include/sysexits.h</filename>). Otherwise, <constant>1</constant> is returned
 340     (<constant>EXIT_FAILURE</constant> from <filename>/usr/include/stdlib.h</filename>).</para>
 341
 342     <para>Note: when creating items, if the target already exists, but is of the wrong type or otherwise does
 343     not match the requested state, and forced operation has not been requested with <literal>+</literal>,
 344     a message is emitted, but the failure is otherwise ignored.</para>
 345   </refsect1>
 346
 347   <refsect1>
 348     <title>See Also</title>
 349     <para>
 350       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 351       <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 352     </para>
 353   </refsect1>
 354
 355 </refentry>