X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsystemd.unit.xml;h=2196e73bb308f5649add04ec20d319b81811cbe0;hb=aa0bb9c2c4500696530957f715e097c00bd9e8c4;hp=35644d38a666c68dd1b7c0d37aeabbca1a624e33;hpb=7a529f63e60dfdccc23d61808c20ba40d9901e47;p=elogind.git
diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml
index 35644d38a..2196e73bb 100644
--- a/man/systemd.unit.xml
+++ b/man/systemd.unit.xml
@@ -48,16 +48,28 @@
- systemd.service,
- systemd.socket,
- systemd.device,
- systemd.mount,
- systemd.automount,
- systemd.swap,
- systemd.target,
- systemd.path,
- systemd.timer,
- systemd.snapshot
+ service.service,
+ socket.socket,
+ device.device,
+ mount.mount,
+ automount.automount,
+ swap.swap,
+ target.target,
+ path.path,
+ timer.timer,
+ snapshot.snapshot
+
+ /etc/systemd/system/*
+/run/systemd/system/*
+/usr/lib/systemd/system/*
+...
+
+
+ /etc/systemd/user/*
+/run/systemd/user/*
+/usr/lib/systemd/user/*
+...
+
@@ -66,7 +78,7 @@
A unit configuration file encodes information
about a service, a socket, a device, a mount point, an
automount point, a swap file or partition, a start-up
- target, a file system path or a timer controlled and
+ target, a file system path, or a timer controlled and
supervised by
systemd1. The
syntax is inspired by 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.
+ information:
+ systemd.service5,
+ systemd.socket5,
+ systemd.device5,
+ systemd.mount5,
+ systemd.automount5,
+ systemd.swap5,
+ systemd.target5,
+ systemd.path5,
+ systemd.timer5,
+ systemd.snapshot5.
+
+
+ Unit files are loaded from a set of paths
+ determined during compilation, described in the next section.
+ Unit files may contain additional options on top
of those listed here. If systemd encounters an unknown
@@ -106,12 +133,14 @@
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. For details see systemd.time7.
+ 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
@@ -119,39 +148,48 @@
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
+ use this functionality only sparingly and instead rely
on techniques such as bus-based or socket-based
- activation which makes dependencies implicit, which
- both results in a simpler and more flexible
- system.
+ activation which make dependencies implicit, resulting
+ in a both simpler and more flexible system.
Some unit names reflect paths existing in the
file system name space. Example: a device unit
@@ -186,124 +224,168 @@
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:
+ 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
+ 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.
+
+
+
+
+ Unit load path
+
+ Unit files are loaded from a set of paths
+ determined during compilation, described in the two
+ tables below. Unit files found in directories higher
+ in the hierarchy override files with the same name
+ lower in the hierarchy, thus allowing overrides.
+
+
+ When systemd is running in session mode
+ () and the variable
+ $SYSTEMD_UNIT_PATH is set, this
+ contents of this variable overrides the unit load
+ path.
+
- Specifiers available in unit files
-
-
-
-
+
+ Load path when running in system mode ().
+
+
+
+
+
- Specifier
- Meaning
- Details
+ Path
+ Description
- %n
- Full unit name
-
+ /run/systemd/generator.early
+ Generated units
- %N
- Unescaped full unit name
-
+ @SYSTEM_CONFIG_UNIT_PATH@
+ Local configuration
- %p
- Prefix name
- This refers to the string before the @, i.e. "getty" in the example above, where "tty3" is the instance name.
+ /etc/systemd/system
- %P
- Unescaped prefix name
-
+ /run/systemd/systemd
+ Volatile units
- %i
- Instance name
- This is the string between the @ character and the suffix.
+ /run/systemd/generator
+ Generated units
- %I
- Unescaped instance name
-
+ /usr/local/lib/systemd/system
+ Units for local packages
- %f
- Unescaped file name
- This is either the unescaped instance name (if set) with / prepended (if necessary), or the prefix name similarly prepended with /.
+ @systemunitdir@
+ Systemd package configuration
- %c
- Control group path of the unit
-
+ /usr/lib/systemd/system
+ Units for installed packages
- %r
- Root control group path of systemd
-
+ /lib/systemd/system
- %R
- Parent directory of the root control group path of systemd
-
+ /run/systemd/generator.late
+ Generated units
+
+
+
+
+
+
+ Load path when running in session mode ().
+
+
+
+
+
+
- %t
- Runtime socket dir
- This is either /run (for the system manager) or $XDG_RUNTIME_DIR (for user managers).
+ Path
+ Description
+
+
- %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.
+ /tmp/systemd-generator.early.XXXXXX
+ Generated units
- %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.
+ @USER_CONFIG_UNIT_PATH@
+ Local configuration
- %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.
+ /etc/systemd/user
- %m
- Machine ID
- The machine ID of the running system, formatted as string. See machine-id5 for more information.
+ /run/systemd/user
+ Volatile units
- %b
- Boot ID
- The boot ID of the running system, formatted as string. See random4 for more information.
+ /tmp/systemd-generator.XXXXXX
+ Generated units
- %H
- Host name
- The host name of the running system.
+ /usr/local/lib/systemd/user
+ Units for local packages
+
+
+ /usr/local/share/systemd/user
+
+
+ @userunitdir@
+ Systemd package configuration
+
+
+ /usr/lib/systemd/user
+ Units for installed packages
+
+
+ /usr/share/systemd/user
+
+
+ /tmp/systemd-generator.late.XXXXXX
+ Generated units
- 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.
+ Note: the paths listed above are set at
+ compilation time and differ between distributions. The
+ "authorative" list is printed by
+ systemd at during start and daemon
+ reconfiguration.
- The unit file format is covered by the
- Interface
- Stability Promise.
+ Additional units might be loaded into systemd
+ ("linked") from directories not on the unit load
+ path. See the link command for
+ systemctl1.
+
@@ -313,7 +395,7 @@
carries generic information about the unit that is not
dependent on the type of unit:
-
+ Description=
@@ -345,8 +427,13 @@
reference documentation that explains
what the unit's purpose is, followed
by how it is configured, followed by
- any other related
- documentation.
+ 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.
@@ -785,6 +872,7 @@
ConditionSecurity=ConditionCapability=ConditionHost=
+ ConditionACPower=ConditionNull=Before starting a unit
@@ -954,6 +1042,23 @@
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
@@ -980,8 +1085,12 @@
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.
@@ -1008,7 +1117,7 @@
systemctl1
tool during installation of a unit:
-
+ Alias=
@@ -1059,6 +1168,140 @@
+ The following specifiers are interpreted in the
+ Install section: %n, %N, %p, %i, %U, %u, %m, %H, %b.
+ For their meaning see the next section.
+
+
+
+
+ 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. If the user is
+ root (UID equal to 0), the
+ shell configured in account database is
+ ignored and /bin/sh is
+ always used.
+
+
+
+ %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.
+
+
+ %%
+ Escaped %
+ Single percent sign.
+
+
+
+