Add a couple of exampels, at least one for each service type that
include some explanations and pointers to various relevant options.
---
man/systemd.service.xml | 332
1 file changed, 332 insertions(+)
diff --git a/man/systemd.service.xml b/man/systemd.service.xml
index 4c890df..5ccbba0 100644
--- a/man/systemd.service.xml
+++ b/man/systemd.service.xml
@@ -1358,6 +1358,338 @@ ExecStart=/bin/echo $ONE $TWO $THREE
+Examples
+
+
+Simple service
+
+The following unit file creates a service
+that will execute
+/usr/sbin/foo-daemon.
+Since no Type= is specified,
+the default
+Type=simple
+will be assumed. systemd will assume the unit
+to be started immediately after the program has
+begun executing.
+
+[Unit]
+Description=Foo
+
+[Service]
+ExecStart=/usr/sbin/foo-daemon
+
+[Install]
+WantedBy=multi-user.target
+
+Note that systemd assumes here that the
+program will continue running in the foreground
+as long as it's active. If the program
+backgrounds/daemonizes/forks itself, please use
+Type=forking
+instead.
+
+Since no ExecStop= was
+specified, systemd will send SIGTERM to all
+processes started from this service, and after
+a timeout also SIGKILL. This behavior can be
+modified, see
+
systemd.kill5
+for details.
+
+Note that this unit type does not include
+any type of notification when a service has
+completed initialization. For this, you should
+use other unit types, such as
+Type=notify
+if the service understands systemd's
+notification protocol,
+Type=forking
+if the service can background itself or
+Type=dbus
+if the unit acquires a DBus name once
+initialization is complete. See below.
+
+
+
+Oneshot service
+
+Sometimes units should just execute an
+action without keeping active processes, such
+as a filesystem check or a cleanup action on
+boot. For this,
+Type=oneshot
+exists. Units of this type will wait until the
+process specified terminates and then fall back
+to being inactive. The following unit will
+perform a clenaup action:
+
+[Unit]
+Description=Cleanup old Foo data
+
+[Service]
+Type=oneshot
+ExecStart=/usr/sbin/foo-cleanup
+
+[Install]
+WantedBy=multi-user.target
+
+Note that systemd will consider the unit
+to be in the state 'starting' until the program
+has terminated, so ordered dependencies will
+wait for the program to finish before starting
+themselves. The unit will revert to the
+'inactive' state after the execution is
+done. That means another request to start the
+unit will perform the action again.
+
+
+
+Stoppable oneshot service
+
+Similarly to the oneshot services, there
+are sometimes units that need to execute a
+program to set up something and then execute
+another to shut it down, but no process remains
+active while they are considered
+'started'. Network configuration can sometimes
+fall into this category.
+
+For this, systemd knows the setting
+
RemainAfterExit=yes,
+which causes systemd to consider the unit to be
+active if the start action exited successfully.
+This directive can be used with all types, but
+is most useful with
+Type=oneshot
+and
+Type=simple.
+With
+
