X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.unit.xml;h=e54cafaabcd2f0b854b7d9e1aa7126c83170d5a5;hp=bb11682fc62e560bff7170d23291d42136bb0232;hb=335aa753fa60ba0bb3c9fe679c761d5f1f3b1588;hpb=b5e9dba8d60b8fb80b6302b6ea2cd665b3ab370c diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml index bb11682fc..e54cafaab 100644 --- a/man/systemd.unit.xml +++ b/man/systemd.unit.xml @@ -189,6 +189,19 @@ respectively. The prefix name here refers to the string before the @, i.e. "getty" in the example above, where "tty3" is the instance name. + + If a unit file is empty (i.e. has the file size + 0) or is symlinked to /dev/null + its configuration will not be loaded and it appears + with a load state of masked, and + cannot be activated. Use this as an effective way to + fully disable a unit, making it impossible to start it + even manually. + + The unit file format is covered by the + Interface + Stability Promise. @@ -418,8 +431,9 @@ Lists one or more units that are activated when this - unit fails (i.e. enters maintenance - state). + unit enters the + 'failed' + state. @@ -484,6 +498,23 @@ . + + AllowIsolate= + + Takes a boolean + argument. If + this unit may be used with the + systemctl isolate + command. Otherwise this will be + refused. It probably is a good idea to + leave this disabled except for target + units that shall be used similar to + runlevels in SysV init systems, just + as a precaution to avoid unusable + system states. This option defaults to + . + + DefaultDependencies= @@ -535,24 +566,67 @@ time. If this time limit is reached the job will be cancelled, the unit however will not change state or even - enter maintenance mode. This value - defaults to 0 (job timeouts disabled), - except for device units. NB: this - timeout is independent from any - unit-specific timeout (for example, - the timeout set with + enter the 'failed' + mode. This value defaults to 0 (job + timeouts disabled), except for device + units. NB: this timeout is independent + from any unit-specific timeout (for + example, the timeout set with Timeout= in service - units) as the job timeout has no effect - on the unit itself, only on the job - that might be pending for it. Or in - other words: unit-specific timeouts + units) as the job timeout has no + effect on the unit itself, only on the + job that might be pending for it. Or + in other words: unit-specific timeouts are useful to abort unit state changes, and revert them. The job timeout set with this option however - is useful to abort only the job waiting - for the unit state to change. + is useful to abort only the job + waiting for the unit state to + change. + + ConditionPathExists= + ConditionKernelCommandLine= + + Before starting a unit + verify that the specified condition is + true. With + ConditionPathExists= + a file existance condition can be + checked before a unit is started. If + the specified absolute path name does + not exist startup of a unit will not + actually happen, however the unit is + still useful for ordering purposes in + this case. The condition is checked at + the time the queued start job is to be + executed. If the absolute path name + passed to + ConditionPathExists= + is prefixed with an exclamation mark + (!), the test is negated, and the unit + only started if the path does not + exist. Similarly + ConditionKernelCommandLine= + may be used to check whether a + specific kernel command line option is + set (or if prefixed with the + exclamation mark unset). The argument + must either be a single word, or an + assignment (i.e. two words, seperated + by the equality sign). In the former + case the kernel command line is search + for the word appearing as is, or as + left hand side of an assignment. In + the latter case the exact assignment + is looked for with right and left hand + side matching. If multiple conditions + are specified the unit will be + executed iff at least one of them + apply (i.e. a logical OR is + applied). + Unit file may include a [Install] section, which