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diff --git a/man/daemon.xml b/man/daemon.xml
index 01ab0f3b5..0d29e7aa1 100644
--- a/man/daemon.xml
+++ b/man/daemon.xml
@@ -8,16 +8,16 @@
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU General Public License
+ You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see .
-->
@@ -44,7 +44,7 @@
daemon
- Writing and Packaging System Daemons
+ Writing and packaging system daemons
@@ -115,14 +115,14 @@
In the child, call
fork() again, to
- ensure the daemon can never re-aquire
+ ensure the daemon can never re-acquire
a terminal again.
Call exit() in the
first child, so that only the second
child (the actual daemon process)
stays around. This ensures that the
- daemon process is reparented to
+ daemon process is re-parented to
init/PID 1, as all daemons should
be.
@@ -181,11 +181,11 @@
exit() in the
original process. The process that
invoked the daemon must be able to
- rely that this
+ rely on that this
exit() happens
after initialization is complete and
all external communication channels
- established and
+ are established and
accessible.
@@ -196,7 +196,7 @@
compatibility with SysV systems should
implement the scheme pointed out
above. However, it is recommended to make this
- behaviour optional and configurable via a
+ behavior optional and configurable via a
command line argument, to ease debugging as
well as to simplify integration into systems
using systemd.
@@ -271,7 +271,7 @@
for details.
As much as possible,
- rely on the init systemd's
+ rely on the init system's
functionality to limit the access of
the daemon to files, services and
other resources. i.e. in the case of
@@ -323,7 +323,7 @@
Instead of using the
syslog() call to log directly to the
- system logger, a new-style daemon may
+ system syslog service, a new-style daemon may
choose to simply log to STDERR via
fprintf(), which is then forwarded to
syslog by the init system. If log
@@ -345,7 +345,7 @@
StandardError=syslog
in the service unit file. For details
see
- sd-daemon7
+ sd-daemon3
and
systemd.exec5.
@@ -384,7 +384,7 @@
communication channels are established already, and no
request is lost because client requests will be queued
by the bus system (in case of D-Bus) or the kernel (in
- case of sockets), until the activation
+ case of sockets), until the activation is
completed.
@@ -397,7 +397,7 @@
url="http://refspecs.freestandards.org/LSB_3.1.1/LSB-Core-generic/LSB-Core-generic/iniscrptact.html">LSB
Linux Standard Base Core
Specification. This method of
- activation is supported ubiquitiously on Linux
+ activation is supported ubiquitously on Linux
init systems, both old-style and new-style
systems. Among other issues SysV init scripts
have the disadvantage of involving shell
@@ -449,7 +449,7 @@
activation of daemons. However, the primary
advantage of this scheme is that all providers
and all consumers of the sockets can be
- started in parallel as soon als all sockets
+ started in parallel as soon as all sockets
are established. In addition to that daemons
can be restarted with losing only a minimal
number of client transactions or even any
@@ -462,13 +462,13 @@
New-style daemons which support socket
activation must be able to receive their
- sockets from the init system, instead of of
+ sockets from the init system, instead of
creating and binding them themselves. For
details about the programming interfaces for
this scheme provided by systemd see
sd_listen_fds3
and
- sd-daemon7. For
+ sd-daemon3. For
details about porting existing daemons to
socket-based activation see below. With
minimal effort it is possible to implement
@@ -543,10 +543,10 @@
the hardware of the respective kind is plugged
in or otherwise becomes available. In a
new-style init system it is possible to bind
- activation to hardware plug/unplug events. In systemd,
- kernel devices appearing in the sysfs/udev
- device tree can be exposed as units if they
- are tagged with the string
+ activation to hardware plug/unplug events. In
+ systemd, kernel devices appearing in the
+ sysfs/udev device tree can be exposed as units
+ if they are tagged with the string
"systemd". Like any other
kind of unit they may then pull in other units
when activated (i.e. Plugged in) and thus
@@ -570,8 +570,9 @@
bluetoothd.service via
controlling a
bluetooth.target.wants/
- symlink uniformly with a tool like
- systemd-install1
+ symlink uniformly with a command like
+ enable of
+ systemctl1
instead of manipulating the udev
ruleset.
@@ -643,7 +644,7 @@
to the CPU and IO schedulers. If a process
executed by the init system shall not
negatively impact the amount of CPU or IO
- bandwith available to other processes, it
+ bandwidth available to other processes, it
should be configured with
CPUSchedulingPolicy=idle
and/or
@@ -678,7 +679,8 @@
If your daemon
registers a D-Bus name on the bus,
make sure to use
- Type=dbus if
+ Type=dbus in the
+ service file if
possible.
Make sure to set a
@@ -704,15 +706,26 @@
system-independent.
Make sure to include
- an [Install] section including
- installation information for the unit
- file. See
+ an [Install]
+ section including installation
+ information for the unit file. See
systemd.unit5
for details. To activate your service
on boot make sure to add a
WantedBy=multi-user.target
or
- WantedBy=graphical.target directive.
+ WantedBy=graphical.target
+ directive. To activate your socket on
+ boot, make sure to add
+ WantedBy=sockets.target. Usually
+ you also want to make sure that when
+ your service is installed your socket
+ is installed too, hence add
+ Also=foo.socket in
+ your service file
+ foo.service, for
+ a hypothetical program
+ foo.
@@ -726,19 +739,20 @@
install their systemd unit files in the
directory returned by pkg-config
systemd
- --variable=systemdsystemnunitdir
- (for system services),
- resp. pkg-config systemd
- --variable=systemdsessionunitdir
- (for session services). This will make the
+ --variable=systemdsystemunitdir (for
+ system services) or pkg-config
+ systemd
+ --variable=systemduserunitdir
+ (for user services). This will make the
services available in the system on explicit
request but not activate them automatically
during boot. Optionally, during package
installation (e.g. rpm -i
by the administrator) symlinks should be
created in the systemd configuration
- directories via the
- systemd-install1
+ directories via the enable
+ command of the
+ systemctl1
tool, to activate them automatically on
boot.
@@ -753,15 +767,17 @@
AC_ARG_WITH([systemdsystemunitdir],
AS_HELP_STRING([--with-systemdsystemunitdir=DIR], [Directory for systemd service files]),
[], [with_systemdsystemunitdir=$($PKG_CONFIG --variable=systemdsystemunitdir systemd)])
-AC_SUBST([systemdsystemunitdir], [$with_systemdsystemunitdir])
-AM_CONDITIONAL(HAVE_SYSTEMD, [test -n "$with_systemdsystemunitdir"])
+if test "x$with_systemdsystemunitdir" != xno; then
+ AC_SUBST([systemdsystemunitdir], [$with_systemdsystemunitdir])
+fi
+AM_CONDITIONAL(HAVE_SYSTEMD, [test -n "$with_systemdsystemunitdir" -a "x$with_systemdsystemunitdir" != xno ])
This snippet allows automatic
installation of the unit files on systemd
machines, and optionally allows their
installation even on machines lacking
systemd. (Modification of this snippet for the
- session unit directory is left as excercise to the
+ user unit directory is left as an exercise for the
reader.)
Additionally, to ensure that
@@ -785,21 +801,73 @@ endif
In the
rpm8
- .spec file use a snippet like
- the following to enable/disable the service
- during installation/deinstallation. Consult
+ .spec file use snippets
+ like the following to enable/disable the
+ service during
+ installation/deinstallation. This makes use of
+ the RPM macros shipped along systemd. Consult
the packaging guidelines of your distribution
for details and the equivalent for other
- package managers:
+ package managers.
+
+ At the top of the file:
+
+ BuildRequires: systemd
+%{?systemd_requires}
+
+ And as scriptlets, further down:
%post
-/usr/bin/systemd-install enable foobar.service foobar.socket >/dev/null 2>&1 || :
+%systemd_post foobar.service foobar.socket
%preun
-if [ "$1" -eq 0 ]; then
- /usr/bin/systemd-install disable foobar.service foobar.socket >/dev/null 2>&1 || :
+%systemd_preun foobar.service foobar.socket
+
+%postun
+%systemd_postun
+
+ If the service shall be restarted during
+ upgrades replace the
+ %postun scriptlet above
+ with the following:
+
+ %postun
+%systemd_postun_with_restart foobar.service
+
+ Note that
+ %systemd_post and
+ %systemd_preun expect the
+ names of all units that are installed/removed
+ as arguments, separated by
+ spaces. %systemd_postun
+ expects no
+ arguments. %systemd_postun_with_restart
+ expects the units to restart as
+ arguments.
+
+ To facilitate upgrades from a package
+ version that shipped only SysV init scripts to
+ a package version that ships both a SysV init
+ script and a native systemd service file, use
+ a fragment like the following:
+
+ %triggerun -- foobar < 0.47.11-1
+if /sbin/chkconfig --level 5 foobar ; then
+ /bin/systemctl --no-reload enable foobar.service foobar.socket >/dev/null 2>&1 || :
fi
+ Where 0.47.11-1 is the first package
+ version that includes the native unit
+ file. This fragment will ensure that the first
+ time the unit file is installed it will be
+ enabled if and only if the SysV init script is
+ enabled, thus making sure that the enable
+ status is not changed. Note that
+ chkconfig is a command
+ specific to Fedora which can be used to check
+ whether a SysV init script is enabled. Other
+ operating systems will have to use different
+ commands here.
@@ -809,8 +877,8 @@ fi
Since new-style init systems such as systemd are
compatible with traditional SysV init systems it is
not strictly necessary to port existing daemons to the
- new style. However doing this offers additional
- functionality to the daemons as well as it simplifies
+ new style. However doing so offers additional
+ functionality to the daemons as well as simplifying
integration into new-style init systems.
To port an existing SysV compatible daemon the
@@ -849,7 +917,7 @@ fi
left-over file descriptors are passed to
executed processes, it might be a good choice
to simply skip the closing of all remaining
- open file descriptors if file descriptors are
+ open file descriptors if sockets are
passed.
Write and install a systemd
@@ -870,8 +938,7 @@ fi
See Also
systemd1,
- systemd-install1,
- sd-daemon7,
+ sd-daemon3,
sd_listen_fds3,
sd_notify3,
daemon3,