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diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml
index bf22ca9bd..953a2897a 100644
--- a/man/systemd.unit.xml
+++ b/man/systemd.unit.xml
@@ -75,13 +75,13 @@
inspired by Microsoft Windows
.ini files.
- This man pages lists the common configuration
+ This man page lists the common configuration
options of all the unit types. These options need to
- be configured in the [Unit] resp. [Install]
- section of the unit files.
+ be configured in the [Unit] or [Install]
+ sections of the unit files.In addition to the generic [Unit] and [Install]
- sections described here, each unit should have a
+ sections described here, each unit may have a
type-specific section, e.g. [Service] for a service
unit. See the respective man pages for more
information.
@@ -106,12 +106,14 @@
Time span values encoded in unit files can be
written in various formats. A stand-alone number
specifies a time in seconds. If suffixed with a time
- unit, the unit is honored. A concatenation of
- multiple values with units is supported, in which case
- the values are added up. Example: "50" refers to 50
+ unit, the unit is honored. A concatenation of multiple
+ values with units is supported, in which case the
+ values are added up. Example: "50" refers to 50
seconds; "2min 200ms" refers to 2 minutes plus 200
milliseconds, i.e. 120200ms. The following time units
- are understood: s, min, h, d, w, ms, us.
+ are understood: s, min, h, d, w, ms, us. For details
+ see
+ systemd.time7.
Empty lines and lines starting with # or ; are
ignored. This may be used for commenting. Lines ending
@@ -119,32 +121,42 @@
line while reading and the backslash is replaced by a
space character. This may be used to wrap long lines.
- If a line starts with
- followed by a file name, the specified file will be
- parsed at this point. Make sure that the file that is
- included has the appropriate section headers before
- any directives.
-
Along with a unit file
- foo.service a directory
+ foo.service the directory
foo.service.wants/ may exist. All
- units symlinked from such a directory are implicitly
- added as dependencies of type
+ unit files symlinked from such a directory are
+ implicitly added as dependencies of type
Wanted= to the unit. This is useful
to hook units into the start-up of other units,
- without having to modify their unit configuration
- files. For details about the semantics of
- Wanted= see below. The preferred
- way to create symlinks in the
- .wants/ directory of a service is
- with the enable command of the
+ without having to modify their unit files. For details
+ about the semantics of Wanted= see
+ below. The preferred way to create symlinks in the
+ .wants/ directory of a unit file
+ is with the enable command of the
systemctl1
tool which reads information from the [Install]
- section of unit files. (See below.) A similar
+ section of unit files (see below). A similar
functionality exists for Requires=
type dependencies as well, the directory suffix is
.requires/ in this case.
+ Along with a unit file
+ foo.service a directory
+ foo.service.d/ may exist. All
+ files with the suffix .conf from
+ this directory will be parsed after the file itself is
+ parsed. This is useful to alter or add configuration
+ settings to a unit, without having to modify their
+ unit files. Make sure that the file that is included
+ has the appropriate section headers before any
+ directive.
+
+ If a line starts with
+ followed by a file name, the specified file will be
+ parsed at this point. Make sure that the file that is
+ included has the appropriate section headers before
+ any directives.
+
Note that while systemd offers a flexible
dependency system between units it is recommended to
use this functionality only sparsely and instead rely
@@ -186,96 +198,7 @@
To refer to the instance string from
within the configuration file you may use the special
%i specifier in many of the
- configuration options. Other specifiers exist, the
- full list is:
-
-
- Specifiers available in unit files
-
-
-
-
-
-
- Specifier
- Meaning
- Details
-
-
-
-
- %n
- Full unit name
-
-
-
- %N
- Unescaped full unit name
-
-
-
- %p
- Prefix name
- This refers to the string before the @, i.e. "getty" in the example above, where "tty3" is the instance name.
-
-
- %P
- Unescaped prefix name
-
-
-
- %i
- Instance name
- This is the string between the @ character and the suffix.
-
-
- %I
- Unescaped instance name
-
-
-
- %f
- Unescaped file name
- This is either the unescaped instance name (if set) with / prepended (if necessary), or the prefix name similarly prepended with /.
-
-
- %c
- Control group path of the unit
-
-
-
- %r
- Root control group path of systemd
-
-
-
- %R
- Parent directory of the root control group path of systemd
-
-
-
- %t
- Runtime socket dir
- This is either /run (for the system manager) or $XDG_RUNTIME_DIR (for user managers).
-
-
- %u
- User name
- This is the name of the configured user of the unit, or (if none is set) the user running the systemd instance.
-
-
- %h
- User home directory
- This is the home directory of the configured user of the unit, or (if none is set) the user running the systemd instance.
-
-
- %s
- User shell
- This is the shell of the configured user of the unit, or (if none is set) the user running the systemd instance.
-
-
-
-
+ configuration options. See below for details.If a unit file is empty (i.e. has the file size
0) or is symlinked to /dev/null
@@ -289,6 +212,7 @@
Interface
Stability Promise.
+
@@ -323,7 +247,20 @@
man:. For more
information about the syntax of these
URIs see
- uri7.
+ uri7. The
+ URIs should be listed in order of
+ relevance, starting with the most
+ relevant. It is a good idea to first
+ reference documentation that explains
+ what the unit's purpose is, followed
+ by how it is configured, followed by
+ any other related documentation. This
+ option may be specified more than once
+ in which case the specified list of
+ URIs is merged. If the empty string is
+ assigned to this option the list is
+ reset and all prior assignments will
+ have no effect.
@@ -403,7 +340,7 @@
Similar to
Requires=
- resp. RequiresOverridable=. However,
+ and RequiresOverridable=, respectively. However,
if a unit listed here is not started
already it will not be started and the
transaction fails
@@ -440,7 +377,7 @@
Configures requirement
dependencies, very similar in style to
Requires=, however
- in addition to this behaviour it also
+ in addition to this behavior it also
declares that this unit is stopped
when any of the units listed suddenly
disappears. Units can suddenly,
@@ -551,7 +488,7 @@
Before=. If two
units have no ordering dependencies
between them they are shut down
- resp. started up simultaneously, and
+ or started up simultaneously, and
no ordering takes
place.
@@ -657,13 +594,13 @@
Takes a boolean
argument. If
this unit can only be activated
- (resp. deactivated) indirectly. In
+ or deactivated indirectly. In
this case explicit start-up
- (resp. termination) requested by the
+ or termination requested by the
user is denied, however if it is
- started (resp. stopped) as a
+ started or stopped as a
dependency of another unit, start-up
- (resp. termination) will succeed. This
+ or termination will succeed. This
is mostly a safety feature to ensure
that the user does not accidentally
activate units that are not intended
@@ -755,12 +692,14 @@
ConditionPathIsMountPoint=ConditionPathIsReadWrite=ConditionDirectoryNotEmpty=
+ ConditionFileNotEmpty=ConditionFileIsExecutable=ConditionKernelCommandLine=ConditionVirtualization=ConditionSecurity=ConditionCapability=ConditionHost=
+ ConditionACPower=ConditionNull=Before starting a unit
@@ -825,21 +764,28 @@
(i.e. not mounted
read-only).
- ConditionFileIsExecutable=
+ ConditionDirectoryNotEmpty=
is similar to
ConditionPathExists=
but verifies whether a certain path
- exists, is a regular file and marked
- executable.
+ exists and is a non-empty
+ directory.
- ConditionDirectoryNotEmpty=
+ ConditionFileNotEmpty=
is similar to
ConditionPathExists=
but verifies whether a certain path
- exists and is a non-empty
- directory.
+ exists and refers to a regular file
+ with a non-zero size.
+
+ ConditionFileIsExecutable=
+ is similar to
+ ConditionPathExists=
+ but verifies whether a certain path
+ exists, is a regular file and marked
+ executable.
- Similarly,
+ Similar,
ConditionKernelCommandLine=
may be used to check whether a
specific kernel command line option is
@@ -923,6 +869,23 @@
The test may be negated by prepending
an exclamation mark.
+ ConditionACPower=
+ may be used to check whether the
+ system has AC power, or is exclusively
+ battery powered at the time of
+ activation of the unit. This takes a
+ boolean argument. If set to
+ true the condition
+ will hold only if at least one AC
+ connector of the system is connected
+ to a power source, or if no AC
+ connectors are known. Conversely, if
+ set to false the
+ condition will hold only if there is
+ at least one AC connector known and
+ all AC connectors are disconnected
+ from a power source.
+
Finally,
ConditionNull= may
be used to add a constant condition
@@ -949,8 +912,12 @@
pipe symbol must be passed first, the
exclamation second. Except for
ConditionPathIsSymbolicLink=,
- all path checks follow
- symlinks.
+ all path checks follow symlinks. If
+ any of these options is assigned the
+ empty string the list of conditions is
+ reset completely, all previous
+ condition settings (of any kind) will
+ have no effect.
@@ -1000,8 +967,8 @@
Installs a symlink in
the .wants/
- resp. .requires/
- subdirectory for a unit. This has the
+ or .requires/
+ subdirectory for a unit, respectively. This has the
effect that when the listed unit name
is activated the unit listing it is
activated
@@ -1030,6 +997,124 @@
+
+ Specifiers
+
+ Many settings resolve specifiers which may be
+ used to write generic unit files referring to runtime
+ or unit parameters that are replaced when the unit
+ files are loaded. The following specifiers are
+ understood:
+
+
+ Specifiers available in unit files
+
+
+
+
+
+
+ Specifier
+ Meaning
+ Details
+
+
+
+
+ %n
+ Full unit name
+
+
+
+ %N
+ Unescaped full unit name
+
+
+
+ %p
+ Prefix name
+ For instantiated units this refers to the string before the @. For non-instantiated units this refers to to the name of the unit with the type suffix removed.
+
+
+ %P
+ Unescaped prefix name
+
+
+
+ %i
+ Instance name
+ For instantiated units: this is the string between the @ character and the suffix.
+
+
+ %I
+ Unescaped instance name
+
+
+
+ %f
+ Unescaped file name
+ This is either the unescaped instance name (if applicable) with / prepended (if applicable), or the prefix name similarly prepended with /.
+
+
+ %c
+ Control group path of the unit
+
+
+
+ %r
+ Root control group path of systemd
+
+
+
+ %R
+ Parent directory of the root control group path of systemd
+
+
+
+ %t
+ Runtime socket dir
+ This is either /run (for the system manager) or $XDG_RUNTIME_DIR (for user managers).
+
+
+ %u
+ User name
+ This is the name of the configured user of the unit, or (if none is set) the user running the systemd instance.
+
+
+ %U
+ User UID
+ This is the UID of the configured user of the unit, or (if none is set) the user running the systemd instance.
+
+
+ %h
+ User home directory
+ This is the home directory of the configured user of the unit, or (if none is set) the user running the systemd instance.
+
+
+ %s
+ User shell
+ This is the shell of the configured user of the unit, or (if none is set) the user running the systemd instance.
+
+
+ %m
+ Machine ID
+ The machine ID of the running system, formatted as string. See machine-id5 for more information.
+
+
+ %b
+ Boot ID
+ The boot ID of the running system, formatted as string. See random4 for more information.
+
+
+ %H
+ Host name
+ The host name of the running system.
+
+
+
+
+
+
See Also
@@ -1046,7 +1131,9 @@
systemd.path5,
systemd.timer5,
systemd.snapshot5,
- capabilities7
+ systemd.time7,
+ capabilities7,
+ systemd.directives7