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Diffstat (limited to 'man/systemd-run.xml')
-rw-r--r-- | man/systemd-run.xml | 93 |
1 files changed, 74 insertions, 19 deletions
diff --git a/man/systemd-run.xml b/man/systemd-run.xml index 245daae946..9c1a29218e 100644 --- a/man/systemd-run.xml +++ b/man/systemd-run.xml @@ -341,10 +341,10 @@ <refsect1> <title>Examples</title> - <para>The following command will log the environment variables - provided by systemd to services:</para> + <example> + <title>Logging environment variables provided by systemd to services</title> - <programlisting># systemd-run env + <programlisting># systemd-run env Running as unit: run-19945.service # journalctl -u run-19945.service Sep 08 07:37:21 bupkis systemd[1]: Starting /usr/bin/env... @@ -352,19 +352,27 @@ Sep 08 07:37:21 bupkis systemd[1]: Started /usr/bin/env. Sep 08 07:37:21 bupkis env[19948]: PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin Sep 08 07:37:21 bupkis env[19948]: LANG=en_US.UTF-8 Sep 08 07:37:21 bupkis env[19948]: BOOT_IMAGE=/vmlinuz-3.11.0-0.rc5.git6.2.fc20.x86_64</programlisting> + </example> - <para>The following command invokes the - <citerefentry project='man-pages'><refentrytitle>updatedb</refentrytitle><manvolnum>8</manvolnum></citerefentry> - tool, but lowers the block I/O weight for it to 10. See - <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> - for more information on the <varname>BlockIOWeight=</varname> - property.</para> + <example> + <title>Limiting resources available to a command</title> - <programlisting># systemd-run -p BlockIOWeight=10 updatedb</programlisting> + <programlisting># systemd-run -p BlockIOWeight=10 updatedb</programlisting> - <para>The following command will touch a file after 30 seconds.</para> + <para>This command invokes the + <citerefentry project='man-pages'><refentrytitle>updatedb</refentrytitle><manvolnum>8</manvolnum></citerefentry> + tool, but lowers the block I/O weight for it to 10. See + <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for more information on the <varname>BlockIOWeight=</varname> + property.</para> + </example> - <programlisting># date; systemd-run --on-active=30 --timer-property=AccuracySec=100ms /bin/touch /tmp/foo + <example> + <title>Running commands at a specified time</title> + + <para>The following command will touch a file after 30 seconds.</para> + + <programlisting># date; systemd-run --on-active=30 --timer-property=AccuracySec=100ms /bin/touch /tmp/foo Mon Dec 8 20:44:24 KST 2014 Running as unit: run-71.timer Will run service as unit: run-71.service @@ -376,13 +384,60 @@ Dec 08 20:44:38 container systemd[1]: Started /bin/touch /tmp/foo. -- Logs begin at Fri 2014-12-05 19:09:21 KST, end at Mon 2014-12-08 20:44:54 KST. -- Dec 08 20:44:48 container systemd[1]: Starting /bin/touch /tmp/foo... Dec 08 20:44:48 container systemd[1]: Started /bin/touch /tmp/foo.</programlisting> - - <para>The following command invokes <filename>/bin/bash</filename> - as a service passing its standard input, output and error to - the calling TTY.</para> - - <programlisting># systemd-run -t --send-sighup /bin/bash</programlisting> - + </example> + + <example> + <title>Allowing access to the tty</title> + + <para>The following command invokes <filename>/bin/bash</filename> as a service + passing its standard input, output and error to the calling TTY.</para> + + <programlisting># systemd-run -t --send-sighup /bin/bash</programlisting> + </example> + + <example> + <title>Start <command>screen</command> as a user service</title> + + <programlisting>$ systemd-run --scope --user screen +Running scope as unit run-r14b0047ab6df45bfb45e7786cc839e76.scope. + +$ screen -ls +There is a screen on: + 492..laptop (Detached) +1 Socket in /var/run/screen/S-fatima. +</programlisting> + + <para>This starts the <command>screen</command> process as a child of the + <command>systemd --user</command> process that was started by + <filename>user@.service</filename>, in a scope unit. A + <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry> + unit is used instead of a + <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> + unit, because <command>screen</command> will exit when detaching from the terminal, + and a service unit would be terminated. Running <command>screen</command> + as a user unit has the advantage that it is not part of the session scope. + If <varname>KillUserProcesses=yes</varname> is configured in + <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + the default, the session scope will be terminated when the user logs + out of that session.</para> + + <para>The <filename>user@.service</filename> is started automatically + when the user first logs in, and stays around as long as at least one + login session is open. After the user logs out of the last session, + <filename>user@.service</filename> and all services underneath it + are terminated. This behaviour is the default, when "lingering" is + not enabled for that user. Enabling lingering means that + <filename>user@.service</filename> is started automatically during + boot, even if the user is not logged in, and that the service is + not terminated when the user logs out.</para> + + <para>Enabling lingering allows the user to run processes without being logged in, + for example to allow <command>screen</command> to persist after the user logs out, + even if the session scope is terminated. In the default configuration, users can + enable lingering for themselves:</para> + + <programlisting>$ loginctl enable-linger</programlisting> + </example> </refsect1> <refsect1> |