man: Add some notes about variable $prefix for StateDirectory=

tl;dr: It isn’t supported.

Wording by Zbigniew Jędrzejewski-Szmek.

See https://twitter.com/pid_eins/status/1102639279614906369 and
https://gitlab.freedesktop.org/libfprint/fprintd/merge_requests/5#note_125536
onwards.

Signed-off-by: Philip Withnall <withnall@endlessm.com>
This commit is contained in:
Philip Withnall 2019-07-03 14:00:48 +01:00 committed by Zbigniew Jędrzejewski-Szmek
parent 52d8bcd131
commit a9a50bd680

View file

@ -972,6 +972,15 @@ CapabilityBoundingSet=~CAP_B CAP_C</programlisting>
configuration or lifetime guarantees, please consider using
<citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
<para>The directories defined by these options are always created under the standard paths used by systemd
(<filename>/var</filename>, <filename>/run</filename>, <filename>/etc</filename>, …). If the service needs
directories in a different location, a different mechanism has to be used to create them.</para>
<para><citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> provides
functionality that overlaps with these options. Using these options is recommended, because the lifetime of
the directories is tied directly to the lifetime of the unit, and it is not necessary to ensure that the
<filename>tmpfiles.d</filename> configuration is executed before the unit is started.</para>
<para>Example: if a system service unit has the following,
<programlisting>RuntimeDirectory=foo/bar baz</programlisting>
the service manager creates <filename>/run/foo</filename> (if it does not exist),