diff options
| -rw-r--r-- | man/systemd.unit.xml | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml index 8f8b5051b8..c5a2c441c7 100644 --- a/man/systemd.unit.xml +++ b/man/systemd.unit.xml @@ -1333,11 +1333,23 @@ <para>If the <varname>systemd.condition-needs-update=</varname> option is specified on the kernel command line (taking a boolean), it will override the result of this condition check, taking - precedence over any file modification time checks. If it is used + precedence over any file modification time checks. If the kernel command line option is used, <filename>systemd-update-done.service</filename> will not have immediate effect on any following <varname>ConditionNeedsUpdate=</varname> checks, until the system is rebooted where the kernel command line option is not specified anymore.</para> - </listitem> + + <para>Note that to make this scheme effective, the timestamp of <filename>/usr/</filename> should + be explicitly updated after its contents are modified. The kernel will automatically update + modification timestamp on a directory only when immediate children of a directory are modified; an + modification of nested files will not automatically result in mtime of <filename>/usr/</filename> + being updated.</para> + + <para>Also note that if the update method includes a call to execute appropriate post-update steps + itself, it should not touch the timestamp of <filename>/usr/</filename>. In a typical distribution + packaging scheme, packages will do any required update steps as part of the installation or + upgrade, to make package contents immediately usable. <varname>ConditionNeedsUpdate=</varname> + should be used with other update mechanisms where such an immediate update does not + happen.</para></listitem> </varlistentry> <varlistentry> |