man: document sd-daemon.[ch]
This commit is contained in:
parent
a3723b97ef
commit
f9378423b9
4
.gitignore
vendored
4
.gitignore
vendored
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@ -16,8 +16,10 @@ systemd-logger
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systemctl
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systemctl
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systemadm
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systemadm
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.dirstamp
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.dirstamp
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*.3
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*.5
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*.5
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*.7
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*.7
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*.8
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*.html
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*.html
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*~
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*~
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*.tar.gz
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*.tar.gz
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@ -45,4 +47,6 @@ stamp-*
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Makefile
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Makefile
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ltmain.sh
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ltmain.sh
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*.tar.bz2
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*.tar.bz2
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*.tar.gz
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*.tar.xz
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libtool
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libtool
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36
Makefile.am
36
Makefile.am
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@ -307,7 +307,13 @@ EXTRA_DIST += \
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dist_man_MANS = \
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dist_man_MANS = \
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man/systemd.unit.5 \
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man/systemd.unit.5 \
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man/systemd.service.5 \
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man/systemd.service.5 \
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man/daemon.7
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man/daemon.7 \
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man/systemd.8 \
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man/sd_notify.3 \
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man/sd_booted.3 \
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man/sd_listen_fds.3 \
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man/sd_is_fifo.3 \
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man/sd-daemon.7
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nodist_man_MANS = \
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nodist_man_MANS = \
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man/systemd.special.7
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man/systemd.special.7
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@ -315,7 +321,13 @@ nodist_man_MANS = \
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dist_noinst_DATA = \
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dist_noinst_DATA = \
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man/systemd.unit.html \
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man/systemd.unit.html \
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man/systemd.service.html \
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man/systemd.service.html \
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man/daemon.html
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man/daemon.html \
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man/systemd.html \
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man/sd_notify.html \
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man/sd_booted.html \
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man/sd_listen_fds.html \
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man/sd_is_fifo.html \
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man/sd-daemon.html
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nodist_noinst_DATA = \
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nodist_noinst_DATA = \
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man/systemd.special.html
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man/systemd.special.html
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@ -326,7 +338,13 @@ EXTRA_DIST += \
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man/systemd.special.xml.in \
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man/systemd.special.xml.in \
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man/systemd.special.7.in \
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man/systemd.special.7.in \
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man/systemd.special.html.in \
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man/systemd.special.html.in \
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man/daemon.xml
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man/daemon.xml \
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man/systemd.xml \
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man/sd_notify.xml \
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man/sd_booted.xml \
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man/sd_listen_fds.xml \
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man/sd_is_fifo.xml \
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man/sd-daemon.xml
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systemd_SOURCES = \
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systemd_SOURCES = \
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src/main.c
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src/main.c
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@ -570,6 +588,12 @@ XSLTPROC_PROCESS_HTML_IN = \
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$(XSLTPROC) -o ${@:.in=} --nonet http://docbook.sourceforge.net/release/xsl/current/xhtml-1_1/docbook.xsl $< && \
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$(XSLTPROC) -o ${@:.in=} --nonet http://docbook.sourceforge.net/release/xsl/current/xhtml-1_1/docbook.xsl $< && \
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mv ${@:.in=} $@
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mv ${@:.in=} $@
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man/%.3: man/%.xml
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$(XSLTPROC_PROCESS_MAN)
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man/%.3.in: man/%.xml.in
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$(XSLTPROC_PROCESS_MAN)
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man/%.5: man/%.xml
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man/%.5: man/%.xml
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$(XSLTPROC_PROCESS_MAN)
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$(XSLTPROC_PROCESS_MAN)
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@ -582,6 +606,12 @@ man/%.7: man/%.xml
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man/%.7.in: man/%.xml.in
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man/%.7.in: man/%.xml.in
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$(XSLTPROC_PROCESS_MAN_IN)
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$(XSLTPROC_PROCESS_MAN_IN)
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man/%.8: man/%.xml
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$(XSLTPROC_PROCESS_MAN)
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man/%.8.in: man/%.xml.in
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$(XSLTPROC_PROCESS_MAN_IN)
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man/%.html: man/%.xml
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man/%.html: man/%.xml
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$(XSLTPROC_PROCESS_HTML)
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$(XSLTPROC_PROCESS_HTML)
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162
man/sd-daemon.xml
Normal file
162
man/sd-daemon.xml
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@ -0,0 +1,162 @@
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<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!--
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This file is part of systemd.
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Copyright 2010 Lennart Poettering
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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|
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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||||||
|
General Public License for more details.
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|
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You should have received a copy of the GNU General Public License
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|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
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-->
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<refentry id="sd-daemon">
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<refentryinfo>
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<title>sd-daemon</title>
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<productname>systemd</productname>
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<authorgroup>
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<author>
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<contrib>Developer</contrib>
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<firstname>Lennart</firstname>
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<surname>Poettering</surname>
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<email>lennart@poettering.net</email>
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</author>
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</authorgroup>
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</refentryinfo>
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<refmeta>
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<refentrytitle>sd-daemon</refentrytitle>
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<manvolnum>7</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>sd-daemon</refname>
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<refpurpose>Reference implementation of APIs for
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new-style daemons</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<funcsynopsis>
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<funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
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</funcsynopsis>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para><filename>sd-daemon.c</filename> and
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<filename>sd-daemon.h</filename> provide a reference
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implementation of various APIs for new-style daemons,
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as implemented by the
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<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
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init system.</para>
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<para>See
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<citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_is_fifo</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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for more information about the functions
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implemented. In addition to these functions a couple
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of logging prefixes are defined as macros:</para>
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<programlisting>#define SD_EMERG "<0>" /* system is unusable */
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#define SD_ALERT "<1>" /* action must be taken immediately */
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#define SD_CRIT "<2>" /* critical conditions */
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#define SD_ERR "<3>" /* error conditions */
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#define SD_WARNING "<4>" /* warning conditions */
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#define SD_NOTICE "<5>" /* normal but significant condition */
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#define SD_INFO "<6>" /* informational */
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#define SD_DEBUG "<7>" /* debug-level messages */</programlisting>
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<para>These prefixes are intended to be used in
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conjunction with STDERR-based logging as implemented
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by systemd. If a systemd service definition file is
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configured with <varname>StandardError=syslog</varname>
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or <varname>StandardError=kmsg</varname> these
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prefixes can be used to encode a log level in lines
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printed. This is similar to the kernel
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<function>printk()</function>-style logging. See
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<citerefentry><refentrytitle>klogctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
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for more information.</para>
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<para>The log levels are identical to
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<citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>'s
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log level system. To use these prefixes simply prefix
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every line with one of these strings. A line that is
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not prefixed will be logged at the default log level
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SD_INFO.</para>
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<example>
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<title>Hello World</title>
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<para>A daemon may log with the log level
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NOTICE by issuing this call:</para>
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<programlisting>fprintf(stderr, SD_NOTICE "Hello World!\n");</programlisting>
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</example>
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</refsect1>
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<refsect1>
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<title>Notes</title>
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<para>These interfaces are provided by the reference
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implementation of APIs for new-style daemons and
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distributed with the systemd package. The algorithms
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they implement are simple, and can easily be
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reimplemented in daemons if it is important to support
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this interface without using the reference
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implementation. See the respective function man pages
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for details.</para>
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<para>In addition, for details about the algorithms
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check the liberally licensed reference implementation
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sources:
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<ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.c"/>
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resp. <ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.h"/></para>
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<para>These APIs are implemented in the reference
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implementation's drop-in
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<filename>sd-daemon.c</filename> and
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<filename>sd-daemon.h</filename> files. It is
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recommended that applications consuming these APIs copy
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the implementation into their source tree, either
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verbatim or in excerpts. These interfaces are
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currently not available in a dynamic library.</para>
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<para>The functions directly related to new-style
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daemons become NOPs when -DDISABLE_SYSTEMD is set
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during compilation. In addition, if
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<filename>sd-daemon.c</filename> is compiled on
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non-Linux systems they become NOPs, too.</para>
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</refsect1>
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<refsect1>
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<title>See Also</title>
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<para>
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<citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>sd_is_fifo</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
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<citerefentry><refentrytitle>fprintf</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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</para>
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</refsect1>
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</refentry>
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122
man/sd_booted.xml
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122
man/sd_booted.xml
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<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!--
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This file is part of systemd.
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|
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Copyright 2010 Lennart Poettering
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|
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systemd is free software; you can redistribute it and/or modify it
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||||||
|
under the terms of the GNU General Public License as published by
|
||||||
|
the Free Software Foundation; either version 2 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.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU General Public License
|
||||||
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
-->
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||||||
|
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<refentry id="sd_booted">
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<refentryinfo>
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<title>sd_booted</title>
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<productname>systemd</productname>
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<authorgroup>
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<author>
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<contrib>Developer</contrib>
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<firstname>Lennart</firstname>
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||||||
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<surname>Poettering</surname>
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<email>lennart@poettering.net</email>
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</author>
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</authorgroup>
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</refentryinfo>
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<refmeta>
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<refentrytitle>sd_booted</refentrytitle>
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<manvolnum>3</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>sd_booted</refname>
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<refpurpose>Test whether the system is running the systemd init system.</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<funcsynopsis>
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<funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
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<funcprototype>
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<funcdef>int <function>sd_booted</function></funcdef>
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<paramdef>void</paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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|
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<refsect1>
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<title>Description</title>
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<para><function>sd_booted()</function> checks whether
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the system was booted up using the systemd init system.</para>
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</refsect1>
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<refsect1>
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<title>Return Value</title>
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<para>On failure, this call returns a negative
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errno-style error code. If the system was booted up
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with systemd as init system this call returns a
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postive return value, zero otherwise.</para>
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</refsect1>
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|
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<refsect1>
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|
<title>Notes</title>
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||||||
|
|
||||||
|
<para>This function is provided by the reference
|
||||||
|
implementation of APIs for new-style daemons and
|
||||||
|
distributed with the systemd package. The algorithm it
|
||||||
|
implements is simple, and can easily be reimplemented
|
||||||
|
in daemons if it is important to support this
|
||||||
|
interface without using the reference
|
||||||
|
implementation.</para>
|
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|
|
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<para>Internally, this function checks whether the
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<filename>/cgroup/systemd</filename> virtual file
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||||||
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system is mounted, by comparing the st_dev value of
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the <function>stat()</function> data of
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<filename>/cgroup</filename> and
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<filename>/cgroup/systemd</filename>.</para>
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||||||
|
|
||||||
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<para>For details about the algorithm check the
|
||||||
|
liberally licensed reference implementation sources:
|
||||||
|
<ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.c"/>
|
||||||
|
resp. <ulink
|
||||||
|
url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.h"/></para>
|
||||||
|
|
||||||
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<para><function>sd_booted()</function> is implemented
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||||||
|
in the reference implementation's drop-in
|
||||||
|
<filename>sd-daemon.c</filename> and
|
||||||
|
<filename>sd-daemon.h</filename> files. It is
|
||||||
|
recommended that applications consuming these APIs
|
||||||
|
copy the implementation into their source tree. For
|
||||||
|
more details about the reference implementation see
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry></para>
|
||||||
|
|
||||||
|
<para>If -DDISABLE_SYSTEMD is set during compilation
|
||||||
|
this function will always return 0 and otherwise
|
||||||
|
become a NOP.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>See Also</title>
|
||||||
|
<para>
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||||||
|
</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
</refentry>
|
199
man/sd_is_fifo.xml
Normal file
199
man/sd_is_fifo.xml
Normal file
|
@ -0,0 +1,199 @@
|
||||||
|
<?xml version='1.0'?> <!--*-nxml-*-->
|
||||||
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
||||||
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
||||||
|
|
||||||
|
<!--
|
||||||
|
This file is part of systemd.
|
||||||
|
|
||||||
|
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
|
||||||
|
(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.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU General Public License
|
||||||
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
-->
|
||||||
|
|
||||||
|
<refentry id="sd_is_fifo">
|
||||||
|
|
||||||
|
<refentryinfo>
|
||||||
|
<title>sd_is_fifo</title>
|
||||||
|
<productname>systemd</productname>
|
||||||
|
|
||||||
|
<authorgroup>
|
||||||
|
<author>
|
||||||
|
<contrib>Developer</contrib>
|
||||||
|
<firstname>Lennart</firstname>
|
||||||
|
<surname>Poettering</surname>
|
||||||
|
<email>lennart@poettering.net</email>
|
||||||
|
</author>
|
||||||
|
</authorgroup>
|
||||||
|
</refentryinfo>
|
||||||
|
|
||||||
|
<refmeta>
|
||||||
|
<refentrytitle>sd_is_fifo</refentrytitle>
|
||||||
|
<manvolnum>3</manvolnum>
|
||||||
|
</refmeta>
|
||||||
|
|
||||||
|
<refnamediv>
|
||||||
|
<refname>sd_is_fifo</refname>
|
||||||
|
<refname>sd_is_socket</refname>
|
||||||
|
<refname>sd_is_socket_inet</refname>
|
||||||
|
<refname>sd_is_socket_unix</refname>
|
||||||
|
<refpurpose>Check the type of a file descriptor</refpurpose>
|
||||||
|
</refnamediv>
|
||||||
|
|
||||||
|
<refsynopsisdiv>
|
||||||
|
<funcsynopsis>
|
||||||
|
<funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_is_fifo</function></funcdef>
|
||||||
|
<paramdef>int <parameter>fd</parameter></paramdef>
|
||||||
|
<paramdef>const char *<parameter>path</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_is_socket</function></funcdef>
|
||||||
|
<paramdef>int <parameter>fd</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>family</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>type</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>listening</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_is_socket_inet</function></funcdef>
|
||||||
|
<paramdef>int <parameter>fd</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>family</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>type</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>listening</parameter></paramdef>
|
||||||
|
<paramdef>uint16_t <parameter>port</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_is_socket_unix</function></funcdef>
|
||||||
|
<paramdef>int <parameter>fd</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>type</parameter></paramdef>
|
||||||
|
<paramdef>int <parameter>listening</parameter></paramdef>
|
||||||
|
<paramdef>const char* <parameter>path</parameter></paramdef>
|
||||||
|
<paramdef>size_t <parameter>length</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
|
||||||
|
</funcsynopsis>
|
||||||
|
</refsynopsisdiv>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Description</title>
|
||||||
|
|
||||||
|
<para><function>sd_is_fifo()</function> may be called
|
||||||
|
to check whether the specified file descriptor refers
|
||||||
|
to a FIFO or pipe. It the <parameter>path</parameter>
|
||||||
|
parameter is not NULL it is checked whether the FIFO
|
||||||
|
is bound to the specified file system path.</para>
|
||||||
|
|
||||||
|
<para><function>sd_is_socket()</function> may be
|
||||||
|
called to check whether the specified file descriptor
|
||||||
|
refers to a socket. It the
|
||||||
|
<parameter>family</parameter> parameter is not
|
||||||
|
AF_UNSPEC it is checked whether the socket is of the
|
||||||
|
specified family (AF_UNIX, AF_INET, ...). If the
|
||||||
|
<parameter>type</parameter> parameter is not 0 it is
|
||||||
|
checked whether the socket is of the specified type
|
||||||
|
(SOCK_STREAM, SOCK_DGRAM, ...). If the
|
||||||
|
<parameter>listening</parameter> parameter is positive
|
||||||
|
it is checked whether the socket is in accepting mode,
|
||||||
|
i.e. <function>listen()</function> has been called for
|
||||||
|
it. If <parameter>listening</parameter> is 0, it is
|
||||||
|
checked whether the socket is not in this mode. If the
|
||||||
|
parameter is negative, no such check is made. The
|
||||||
|
<parameter>listening</parameter> parameter should only
|
||||||
|
be used for stream sockets and should be set to a
|
||||||
|
negative value otherwise.</para>
|
||||||
|
|
||||||
|
<para><function>sd_is_socket_inet()</function> is
|
||||||
|
similar to <function>sd_is_socket()</function>, but
|
||||||
|
optionally checks the IPv4 or IPv6 port number the
|
||||||
|
socket is bound to, unless <parameter>port</parameter>
|
||||||
|
is zero. For this call <parameter>family</parameter>
|
||||||
|
must be passed as either AF_UNSPEC, AF_INET or
|
||||||
|
AF_INET6.</para>
|
||||||
|
|
||||||
|
<para><function>sd_is_socket_unix()</function> is
|
||||||
|
similar to <function>sd_is_socket()</function>, but
|
||||||
|
optionally checks the AF_UNIX path the socket is bound
|
||||||
|
to, unless the <parameter>path</parameter> parameter
|
||||||
|
is NULL. For normal file system AF_UNIX sockets set
|
||||||
|
the <parameter>length</parameter> parameter to 0. For
|
||||||
|
Linux abstract namespace sockets set the
|
||||||
|
<parameter>length</parameter> to the size of the
|
||||||
|
address, including the initial 0 byte and set
|
||||||
|
<parameter>path</parameter> to the initial 0 byte of
|
||||||
|
the socket address.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Return Value</title>
|
||||||
|
|
||||||
|
<para>On failure, these calls return a negative
|
||||||
|
errno-style error code. If the file descriptor is of
|
||||||
|
the specified type and bound to the specified address
|
||||||
|
a positive return value is returned, otherwise
|
||||||
|
zero.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Notes</title>
|
||||||
|
|
||||||
|
<para>These functions are provided by the reference
|
||||||
|
implementation of APIs for new-style daemons and
|
||||||
|
distributed with the systemd package. The algorithms
|
||||||
|
they implement are simple, and can easily be
|
||||||
|
reimplemented in daemons if it is important to support
|
||||||
|
this interface without using the reference
|
||||||
|
implementation.</para>
|
||||||
|
|
||||||
|
<para>Internally, these function use a combination of
|
||||||
|
<filename>fstat()</filename> and
|
||||||
|
<filename>getsockname()</filename> to check the file
|
||||||
|
descriptor type and where it is bound to.</para>
|
||||||
|
|
||||||
|
<para>For details about the algorithm check the
|
||||||
|
liberally licensed reference implementation sources:
|
||||||
|
<ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.c"/>
|
||||||
|
resp. <ulink
|
||||||
|
url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.h"/></para>
|
||||||
|
|
||||||
|
<para><function>sd_is_fifo()</function> and the
|
||||||
|
related functions are implemented in the reference
|
||||||
|
implementation's drop-in
|
||||||
|
<filename>sd-daemon.c</filename> and
|
||||||
|
<filename>sd-daemon.h</filename> files. It is
|
||||||
|
recommended that applications consuming these APIs
|
||||||
|
copy the implementation into their source tree. For
|
||||||
|
more details about the reference implementation see
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry></para>
|
||||||
|
|
||||||
|
<para>These functions continue to work as described,
|
||||||
|
even if -DDISABLE_SYSTEMD is set during
|
||||||
|
compilation.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>See Also</title>
|
||||||
|
<para>
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||||||
|
</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
</refentry>
|
178
man/sd_listen_fds.xml
Normal file
178
man/sd_listen_fds.xml
Normal file
|
@ -0,0 +1,178 @@
|
||||||
|
<?xml version='1.0'?> <!--*-nxml-*-->
|
||||||
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
||||||
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
||||||
|
|
||||||
|
<!--
|
||||||
|
This file is part of systemd.
|
||||||
|
|
||||||
|
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
|
||||||
|
(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.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU General Public License
|
||||||
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
-->
|
||||||
|
|
||||||
|
<refentry id="sd_listen_fds">
|
||||||
|
|
||||||
|
<refentryinfo>
|
||||||
|
<title>sd_listen_fds</title>
|
||||||
|
<productname>systemd</productname>
|
||||||
|
|
||||||
|
<authorgroup>
|
||||||
|
<author>
|
||||||
|
<contrib>Developer</contrib>
|
||||||
|
<firstname>Lennart</firstname>
|
||||||
|
<surname>Poettering</surname>
|
||||||
|
<email>lennart@poettering.net</email>
|
||||||
|
</author>
|
||||||
|
</authorgroup>
|
||||||
|
</refentryinfo>
|
||||||
|
|
||||||
|
<refmeta>
|
||||||
|
<refentrytitle>sd_listen_fds</refentrytitle>
|
||||||
|
<manvolnum>3</manvolnum>
|
||||||
|
</refmeta>
|
||||||
|
|
||||||
|
<refnamediv>
|
||||||
|
<refname>sd_listen_fds</refname>
|
||||||
|
<refpurpose>Check for file descriptors passed by the init system.</refpurpose>
|
||||||
|
</refnamediv>
|
||||||
|
|
||||||
|
<refsynopsisdiv>
|
||||||
|
<funcsynopsis>
|
||||||
|
<funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
|
||||||
|
|
||||||
|
<funcsynopsisinfo>#define SD_LISTEN_FDS_START 3</funcsynopsisinfo>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_listen_fds</function></funcdef>
|
||||||
|
<paramdef>int <parameter>unset_environment</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
</funcsynopsis>
|
||||||
|
</refsynopsisdiv>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Description</title>
|
||||||
|
|
||||||
|
<para><function>sd_listen_fds()</function> shall be
|
||||||
|
called by a daemon to check for file descriptors
|
||||||
|
passed by the init system as part of the socket-based
|
||||||
|
activation logic.</para>
|
||||||
|
|
||||||
|
<para>If the <parameter>unset_environment</parameter>
|
||||||
|
parameter is non-zero
|
||||||
|
<function>sd_listen_fds()</function> will unset the
|
||||||
|
<varname>$LISTEN_FDS</varname>/<varname>$LISTEN_PID</varname>
|
||||||
|
environment variables before returning (regardless
|
||||||
|
whether the function call itself succeeded or
|
||||||
|
not). Further calls to
|
||||||
|
<function>sd_listen_fds()</function> will then fail,
|
||||||
|
but the variables are no longer inherited by child
|
||||||
|
processes.</para>
|
||||||
|
|
||||||
|
<para>If a daemon receives more than one file
|
||||||
|
descriptor, they will be passed in the same order as
|
||||||
|
configured in the systemd socket definition
|
||||||
|
file. Nonetheless it is recommended to verify the
|
||||||
|
correct socket types before using them. To simplify
|
||||||
|
this checking the functions
|
||||||
|
<citerefentry><refentrytitle>sd_is_fifo</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket_inet</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket_unix</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
||||||
|
are provided. In order to maximize flexibility it is
|
||||||
|
recommened to make these checks as loose as possible
|
||||||
|
without allowing incorrect setups. i.e. often the
|
||||||
|
actual port number a socket is bound to matters little
|
||||||
|
for the service to work, hence it should not be
|
||||||
|
verified. On the other hand, whether a socket is a
|
||||||
|
datagram or stream socket matters a lot for the most
|
||||||
|
common program logics and should hence be
|
||||||
|
checked.</para>
|
||||||
|
|
||||||
|
<para>This function call will set the FD_CLOEXEC flag
|
||||||
|
for all passed file descriptors to avoid further
|
||||||
|
inheritance to children of the calling process.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Return Value</title>
|
||||||
|
|
||||||
|
<para>On failure, this call returns a negative
|
||||||
|
errno-style error code. If
|
||||||
|
<varname>$LISTEN_FDS</varname>/<varname>$LISTEN_PID</varname>
|
||||||
|
was not set or not correctly set for this daemon and
|
||||||
|
hence no file descriptors received 0 is
|
||||||
|
returned. Otherwise the number of file descriptors
|
||||||
|
passed is returned, the application may find them
|
||||||
|
starting with file descriptor SD_LISTEN_FDS_START,
|
||||||
|
i.e. file descriptor 3.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Notes</title>
|
||||||
|
|
||||||
|
<para>This function is provided by the reference
|
||||||
|
implementation of APIs for new-style daemons and
|
||||||
|
distributed with the systemd package. The algorithm it
|
||||||
|
implements is simple, and can easily be reimplemented
|
||||||
|
in daemons if it is important to support this
|
||||||
|
interface without using the reference
|
||||||
|
implementation.</para>
|
||||||
|
|
||||||
|
<para>Internally, this function checks whether the
|
||||||
|
<varname>$LISTEN_PID</varname> environment variable
|
||||||
|
equals the daemon PID. If not, it returns
|
||||||
|
immediately. Otherwise it parses the number passed in
|
||||||
|
the <varname>$LISTEN_FDS</varname> environment
|
||||||
|
variable, then sets the FD_CLOEXEC flag for the parsed
|
||||||
|
number of file descriptors starting from
|
||||||
|
SD_LISTEN_FDS_START. Finally it returns the parsed
|
||||||
|
number.</para>
|
||||||
|
|
||||||
|
<para>For details about the algorithm check the
|
||||||
|
liberally licensed reference implementation sources:
|
||||||
|
<ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.c"/>
|
||||||
|
resp. <ulink
|
||||||
|
url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.h"/></para>
|
||||||
|
|
||||||
|
<para><function>sd_listen_fds()</function> is
|
||||||
|
implemented in the reference implementation's drop-in
|
||||||
|
<filename>sd-daemon.c</filename> and
|
||||||
|
<filename>sd-daemon.h</filename> files. It is
|
||||||
|
recommended that applications consuming these APIs
|
||||||
|
copy the implementation into their source tree. For
|
||||||
|
more details about the reference implementation see
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry></para>
|
||||||
|
|
||||||
|
<para>If -DDISABLE_SYSTEMD is set during compilation
|
||||||
|
this function will always return 0 and otherwise
|
||||||
|
become a NOP.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>See Also</title>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_fifo</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket_inet</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>sd_is_socket_unix</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||||||
|
</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
</refentry>
|
277
man/sd_notify.xml
Normal file
277
man/sd_notify.xml
Normal file
|
@ -0,0 +1,277 @@
|
||||||
|
<?xml version='1.0'?> <!--*-nxml-*-->
|
||||||
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
||||||
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
||||||
|
|
||||||
|
<!--
|
||||||
|
This file is part of systemd.
|
||||||
|
|
||||||
|
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
|
||||||
|
(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.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU General Public License
|
||||||
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
-->
|
||||||
|
|
||||||
|
<refentry id="sd_notify">
|
||||||
|
|
||||||
|
<refentryinfo>
|
||||||
|
<title>sd_notify</title>
|
||||||
|
<productname>systemd</productname>
|
||||||
|
|
||||||
|
<authorgroup>
|
||||||
|
<author>
|
||||||
|
<contrib>Developer</contrib>
|
||||||
|
<firstname>Lennart</firstname>
|
||||||
|
<surname>Poettering</surname>
|
||||||
|
<email>lennart@poettering.net</email>
|
||||||
|
</author>
|
||||||
|
</authorgroup>
|
||||||
|
</refentryinfo>
|
||||||
|
|
||||||
|
<refmeta>
|
||||||
|
<refentrytitle>sd_notify</refentrytitle>
|
||||||
|
<manvolnum>3</manvolnum>
|
||||||
|
</refmeta>
|
||||||
|
|
||||||
|
<refnamediv>
|
||||||
|
<refname>sd_notify</refname>
|
||||||
|
<refname>sd_notifyf</refname>
|
||||||
|
<refpurpose>Notify init system about start-up completion and other daemon status changes</refpurpose>
|
||||||
|
</refnamediv>
|
||||||
|
|
||||||
|
<refsynopsisdiv>
|
||||||
|
<funcsynopsis>
|
||||||
|
<funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_notify</function></funcdef>
|
||||||
|
<paramdef>int <parameter>unset_environment</parameter></paramdef>
|
||||||
|
<paramdef>const char *<parameter>state</parameter></paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
|
||||||
|
<funcprototype>
|
||||||
|
<funcdef>int <function>sd_notifyf</function></funcdef>
|
||||||
|
<paramdef>int <parameter>unset_environment</parameter></paramdef>
|
||||||
|
<paramdef>const char *<parameter>format</parameter></paramdef>
|
||||||
|
<paramdef>...</paramdef>
|
||||||
|
</funcprototype>
|
||||||
|
</funcsynopsis>
|
||||||
|
</refsynopsisdiv>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Description</title>
|
||||||
|
<para><function>sd_notify()</function> shall be called
|
||||||
|
by a daemon to notify the init system about status
|
||||||
|
changes. It can be used to send arbitrary information,
|
||||||
|
encoded in an environment-block-like string. Most
|
||||||
|
importantly it can be used for start-up completion
|
||||||
|
notification.</para>
|
||||||
|
|
||||||
|
<para>If the <parameter>unset_environment</parameter>
|
||||||
|
parameter is non-zero <function>sd_notify()</function>
|
||||||
|
will unset the <varname>$NOTIFY_SOCKET</varname>
|
||||||
|
environment variable before returning (regardless
|
||||||
|
whether the function call itself succeeded or
|
||||||
|
not). Further calls to
|
||||||
|
<function>sd_notify()</function> will then fail, but
|
||||||
|
the variable is no longer inherited by child
|
||||||
|
processes.</para>
|
||||||
|
|
||||||
|
<para>The <parameter>state</parameter> parameter
|
||||||
|
should contain an newline-seperated list of variable
|
||||||
|
assignments, similar in style to an environment
|
||||||
|
block. A trailing newline is implied if none is
|
||||||
|
specified. The string may contain any kind of variable
|
||||||
|
assignments, but the following shall be considered
|
||||||
|
well-known:</para>
|
||||||
|
|
||||||
|
<variablelist>
|
||||||
|
<varlistentry>
|
||||||
|
<term>READY=1</term>
|
||||||
|
|
||||||
|
<listitem><para>Tells the init system
|
||||||
|
that daemon startup is finished. This
|
||||||
|
is only used by systemd if the service
|
||||||
|
definition file has Type=notify
|
||||||
|
set. The passed argument is a boolean
|
||||||
|
"1" or "0". Since there is little
|
||||||
|
value in signalling non-readiness the
|
||||||
|
only value daemons should send is
|
||||||
|
"READY=1".</para></listitem>
|
||||||
|
</varlistentry>
|
||||||
|
|
||||||
|
<varlistentry>
|
||||||
|
<term>STATUS=...</term>
|
||||||
|
|
||||||
|
<listitem><para>Passes a single-line
|
||||||
|
status string back to the init system
|
||||||
|
that describes the daemon state. This
|
||||||
|
is free-from and can be used for
|
||||||
|
various purposes: general state
|
||||||
|
feedback, fsck-like programs could
|
||||||
|
pass completion percentages and
|
||||||
|
failing programs could pass a human
|
||||||
|
readable error message. Example:
|
||||||
|
"STATUS=Completed 66% of file system
|
||||||
|
check..."</para></listitem>
|
||||||
|
</varlistentry>
|
||||||
|
|
||||||
|
<varlistentry>
|
||||||
|
<term>ERRNO=...</term>
|
||||||
|
|
||||||
|
<listitem><para>If a daemon fails, the
|
||||||
|
errno-style error code, formatted as
|
||||||
|
string. Example: "ERRNO=2" for
|
||||||
|
ENOENT.</para></listitem>
|
||||||
|
</varlistentry>
|
||||||
|
|
||||||
|
<varlistentry>
|
||||||
|
<term>BUSERROR=...</term>
|
||||||
|
|
||||||
|
<listitem><para>If a daemon fails, the
|
||||||
|
D-Bus error-style error code. Example:
|
||||||
|
"BUSERROR=org.freedesktop.DBus.Error.TimedOut"</para></listitem>
|
||||||
|
</varlistentry>
|
||||||
|
|
||||||
|
<varlistentry>
|
||||||
|
<term>MAINPID=...</term>
|
||||||
|
|
||||||
|
<listitem><para>The main pid of the
|
||||||
|
daemon, in case the init system did
|
||||||
|
not fork off the process
|
||||||
|
itself. Example:
|
||||||
|
"MAINPID=4711"</para></listitem>
|
||||||
|
</varlistentry>
|
||||||
|
</variablelist>
|
||||||
|
|
||||||
|
<para>It is recommened to prefix variable names that
|
||||||
|
are not shown in the list above with
|
||||||
|
<varname>X_</varname> to avoid namespace
|
||||||
|
clashes.</para>
|
||||||
|
|
||||||
|
<para>Note that systemd will accept status data sent
|
||||||
|
from a daemon only if the
|
||||||
|
<varname>NotifyAccess=</varname> option is correctly
|
||||||
|
set in the service definition file. See
|
||||||
|
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||||||
|
for details.</para>
|
||||||
|
|
||||||
|
<para><function>sd_notifyf()</function> is similar to
|
||||||
|
<function>sd_notifyf()</function> but takes a
|
||||||
|
<function>printf()</function>-like format string plus
|
||||||
|
arguments.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Return Value</title>
|
||||||
|
|
||||||
|
<para>On failure, these calls return a negative
|
||||||
|
errno-style error code. If
|
||||||
|
<varname>$NOTIFY_SOCKET</varname> was not set and
|
||||||
|
hence no status data could be sent 0 is returned. If
|
||||||
|
the status was sent these functions return with a
|
||||||
|
positive return value. In order to support both init
|
||||||
|
systems that implement this scheme and those which
|
||||||
|
don't it is generally recommended to ignore the return
|
||||||
|
value of this call.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Notes</title>
|
||||||
|
|
||||||
|
<para>These functions are provided by the reference
|
||||||
|
implementation of APIs for new-style daemons and
|
||||||
|
distributed with the systemd package. The algorithms
|
||||||
|
they implement are simple, and can easily be
|
||||||
|
reimplemented in daemons if it is important to support
|
||||||
|
this interface without using the reference
|
||||||
|
implementation.</para>
|
||||||
|
|
||||||
|
<para>Internally, these functions send a single
|
||||||
|
datagram with the state string as payload to the
|
||||||
|
AF_UNIX socket referenced in the
|
||||||
|
<varname>$NOTIFY_SOCKET</varname> environment
|
||||||
|
variable. If the first character of
|
||||||
|
<varname>$NOTIFY_SOCKET</varname> is @ the string is
|
||||||
|
understood as Linux abstract namespace socket. The
|
||||||
|
datagram is accompanied by the process credentials of
|
||||||
|
the sending daemon, using SCM_CREDENTIALS.</para>
|
||||||
|
|
||||||
|
<para>For details about the algorithm check the
|
||||||
|
liberally licensed reference implementation sources:
|
||||||
|
<ulink url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.c"/>
|
||||||
|
resp. <ulink
|
||||||
|
url="http://cgit.freedesktop.org/systemd/tree/src/sd-daemon.h"/></para>
|
||||||
|
|
||||||
|
<para><function>sd_notify()</function> and
|
||||||
|
<function>sd_notifyf()</function> are implemented in
|
||||||
|
the reference implementation's drop-in
|
||||||
|
<filename>sd-daemon.c</filename> and
|
||||||
|
<filename>sd-daemon.h</filename> files. It is
|
||||||
|
recommended that applications consuming these APIs
|
||||||
|
copy the implementation into their source tree. For
|
||||||
|
more details about the reference implementation see
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry></para>
|
||||||
|
|
||||||
|
<para>If -DDISABLE_SYSTEMD is set during compilation
|
||||||
|
this function will always return 0 and otherwise
|
||||||
|
become a NOP.</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>Examples</title>
|
||||||
|
|
||||||
|
<example>
|
||||||
|
<title>Start-up Notification</title>
|
||||||
|
|
||||||
|
<para>When a daemon finished starting up, it
|
||||||
|
might issue the following call call to notify
|
||||||
|
the init system:</para>
|
||||||
|
|
||||||
|
<programlisting>sd_notify(0, "READY=1");</programlisting>
|
||||||
|
</example>
|
||||||
|
|
||||||
|
<example>
|
||||||
|
<title>Extended Start-up Notification</title>
|
||||||
|
|
||||||
|
<para>A daemon could send the following after
|
||||||
|
completing initialization:</para>
|
||||||
|
|
||||||
|
<programlisting>sd_notifyf(0, "READY=1\n"
|
||||||
|
"STATUS=Processing requests...\n"
|
||||||
|
"MAINPID=%lu",
|
||||||
|
(unsigned long) getpid());</programlisting>
|
||||||
|
</example>
|
||||||
|
|
||||||
|
<example>
|
||||||
|
<title>Error Cause Notification</title>
|
||||||
|
|
||||||
|
<para>A daemon could send the following shortly before exiting, on failure</para>
|
||||||
|
|
||||||
|
<programlisting>sd_notifyf(0, "STATUS=Failed to start up: %s\n"
|
||||||
|
"ERRNO=%i",
|
||||||
|
strerror(errno),
|
||||||
|
errno);</programlisting>
|
||||||
|
</example>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
<refsect1>
|
||||||
|
<title>See Also</title>
|
||||||
|
<para>
|
||||||
|
<citerefentry><refentrytitle>sd_daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
||||||
|
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||||||
|
</para>
|
||||||
|
</refsect1>
|
||||||
|
|
||||||
|
</refentry>
|
|
@ -76,7 +76,7 @@ extern "C" {
|
||||||
/*
|
/*
|
||||||
Log levels for usage on stderr:
|
Log levels for usage on stderr:
|
||||||
|
|
||||||
fprintf(stderr, SD_NOTICE "Hello World!");
|
fprintf(stderr, SD_NOTICE "Hello World!\n");
|
||||||
|
|
||||||
This is similar to printk() usage in the kernel.
|
This is similar to printk() usage in the kernel.
|
||||||
*/
|
*/
|
||||||
|
@ -158,9 +158,9 @@ int sd_is_socket_inet(int fd, int family, int type, int listening, uint16_t port
|
||||||
int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length) _sd_hidden_;
|
int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length) _sd_hidden_;
|
||||||
|
|
||||||
/*
|
/*
|
||||||
Informs systemd about changed daemon state. This takes a numeber of
|
Informs systemd about changed daemon state. This takes a number of
|
||||||
newline seperated environment-style variable assignments in a
|
newline seperated environment-style variable assignments in a
|
||||||
string. The following strings are known:
|
string. The following variables are known:
|
||||||
|
|
||||||
READY=1 Tells systemd that daemon startup is finished (only
|
READY=1 Tells systemd that daemon startup is finished (only
|
||||||
relevant for services of Type=notify). The passed
|
relevant for services of Type=notify). The passed
|
||||||
|
@ -185,7 +185,8 @@ int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t
|
||||||
MAINPID=... The main pid of a daemon, in case systemd did not
|
MAINPID=... The main pid of a daemon, in case systemd did not
|
||||||
fork off the process itself. Example: "MAINPID=4711"
|
fork off the process itself. Example: "MAINPID=4711"
|
||||||
|
|
||||||
Daemons can choose to send additional variables.
|
Daemons can choose to send additional variables. However, it is
|
||||||
|
recommened to prefix variable names not listed above with X_.
|
||||||
|
|
||||||
Returns a negative errno-style error code on failure. Returns > 0
|
Returns a negative errno-style error code on failure. Returns > 0
|
||||||
if systemd could be notified, 0 if it couldn't possibly because
|
if systemd could be notified, 0 if it couldn't possibly because
|
||||||
|
|
Loading…
Reference in a new issue