man: clarify what “failed” means

systemd.service(5)’s documentation of `ExecCondition=` uses “failed” with
respect to the unit active state.
In particular the unit won’t be considered failed when `ExecCondition=`’s
command exits with a status of 1 through 254 (inclusive). It will however, when
it exits with 255 or abnormally (e.g. timeout, killed by a signal, etc.).

The table “Defined $SERVICE_RESULT values” in systemd.exec(5) uses “failed”
however rather with respect to the condition.

Tests seem to have shown that, if the exit status of the `ExecCondition=`
command is one of 1 through 254 (inclusive), `$SERVICE_RESULT` will be
`exec-condition`, if it is 255, `$SERVICE_RESULT` will be `exit-code` (but
`$EXIT_CODE` and `$EXIT_STATUS` will be empty or unset), if it’s killed because
of `SIGKILL`, `$SERVICE_RESULT` will `signal` and if it times out,
`$SERVICE_RESULT` will be `timeout`.

This commit clarifies the table at least for the case of an exit status of 1
through 254 (inclusive).
The others (signal, timeout and 255 are probably also still ambiguous (e.g.
`signal` uses “A service process”, which could be considered as the actual
service process only).

Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>
(cherry picked from commit 07f471824288433d17ebe097e94dfca85e74fea6)

diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index c0c147045e2ca06a2a68d80e376794596111eeec..812260587f33b369e57fbc41cce9020a98f09085 100644 (file)
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -4351,7 +4351,7 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX
                 </row>
                 <row>
                   <entry><literal>exec-condition</literal></entry>
-                  <entry>Service did not run because <varname>ExecCondition=</varname> failed.</entry>
+                  <entry>Service did not run because <varname>ExecCondition=</varname> failed (that is its command exited with an exit status of 1 through 254 (inclusive)).</entry>
                 </row>
                 <row>
                   <entry><literal>oom-kill</literal></entry>