X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fdaemon.xml;h=de362c1b71466f754a5a4473079f6357bd617af7;hp=46988ef5ec14607ed286bc3a7e517492bd8808a0;hb=909f413d3c572baadf9b13e36e1e90beba42af86;hpb=20ed3656786a36f58a27901356e67d03cdd6de5e diff --git a/man/daemon.xml b/man/daemon.xml index 46988ef5e..de362c1b7 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. @@ -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 @@ -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 @@ -547,7 +547,7 @@ 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 + systemd. Like any other kind of unit they may then pull in other units when activated (i.e. Plugged in) and thus implement device-based activation. Systemd @@ -644,7 +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 @@ -705,24 +705,6 @@ operating system-independent. - Since not all syslog - implementations are socket-activatable - yet, it is recommended to place an - After=syslog.target - dependency in service files for - daemons that can log to - syslog. syslog.target - then either pulls in the syslog daemon - itself or simply the activation - socket. A Wants= or - even Requires= - dependency should generally not be - added, since it should be up to the - administrator whether he wants to - enable logging or not, and most syslog - clients work fine if no log daemon is - running. - Make sure to include an [Install] section including installation @@ -758,10 +740,10 @@ directory returned by pkg-config systemd --variable=systemdsystemunitdir (for - system services), resp. pkg-config + system services) or pkg-config systemd - --variable=systemdsessionunitdir - (for session services). This will make the + --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 @@ -795,7 +777,7 @@ AM_CONDITIONAL(HAVE_SYSTEMD, [test -n "$with_systemdsystemunitdir" -a "x$with_sy 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 @@ -819,45 +801,49 @@ 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. - %post -if [ $1 -eq 1 ]; then - # On install, enable (but don't start) the units by default - /bin/systemctl enable foobar.service foobar.socket >/dev/null 2>&1 || : + At the top of the file: - # Alternatively, just call /bin/systemctl daemon-reload here, - # if the daemon should not be enabled by default on package - # installation -fi + BuildRequires: systemd +%{?systemd_requires} + + And as scriptlets, further down: + + %post +%systemd_post foobar.service foobar.socket %preun -if [ $1 -eq 0 ]; then - # On uninstall, disable and stop the units - /bin/systemctl disable foobar.service foobar.socket >/dev/null 2>&1 || : - /bin/systemctl stop foobar.service foobar.socket >/dev/null 2>&1 || : -fi +%systemd_preun foobar.service foobar.socket %postun -# On upgrade and uninstall, reload init system configuration, to make systemd honour changed unit files -/bin/systemctl daemon-reload >/dev/null 2>&1 || : -if [ $1 -ge 1 ] ; then - # Optionally, on upgrade, restart the daemon - /bin/systemctl try-restart foobar.service >/dev/null 2>&1 || : -fi - - Depending on whether your service should - or should not be started/stopped/restarted - during package installation, deinstallation or - upgrade, a different set of commands may be - specified. See - systemctl1 - for details. +%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 @@ -866,8 +852,8 @@ fi a fragment like the following: %triggerun -- foobar < 0.47.11-1 -if /sbin/chkconfig foobar ; then - /bin/systemctl enable foobar.service foobar.socket >/dev/null 2>&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 @@ -919,7 +905,7 @@ fi sd_listen_fds() returns a positive value), skip the socket creation step and use the passed sockets. Secondly, ensure - that the file-system socket nodes for local + that the file system socket nodes for local AF_UNIX sockets used in the socket-based activation are not removed when the daemon shuts down, if sockets have been @@ -952,7 +938,7 @@ fi See Also systemd1, - sd-daemon7, + sd-daemon3, sd_listen_fds3, sd_notify3, daemon3,