systemctl
systemadm
.dirstamp
+*.3
*.5
*.7
+*.8
*.html
*~
*.tar.gz
Makefile
ltmain.sh
*.tar.bz2
+*.tar.gz
+*.tar.xz
libtool
dist_man_MANS = \
man/systemd.unit.5 \
man/systemd.service.5 \
- man/daemon.7
+ man/daemon.7 \
+ man/systemd.8 \
+ man/sd_notify.3 \
+ man/sd_booted.3 \
+ man/sd_listen_fds.3 \
+ man/sd_is_fifo.3 \
+ man/sd-daemon.7
nodist_man_MANS = \
man/systemd.special.7
dist_noinst_DATA = \
man/systemd.unit.html \
man/systemd.service.html \
- man/daemon.html
+ man/daemon.html \
+ man/systemd.html \
+ man/sd_notify.html \
+ man/sd_booted.html \
+ man/sd_listen_fds.html \
+ man/sd_is_fifo.html \
+ man/sd-daemon.html
nodist_noinst_DATA = \
man/systemd.special.html
man/systemd.special.xml.in \
man/systemd.special.7.in \
man/systemd.special.html.in \
- man/daemon.xml
+ man/daemon.xml \
+ man/systemd.xml \
+ man/sd_notify.xml \
+ man/sd_booted.xml \
+ man/sd_listen_fds.xml \
+ man/sd_is_fifo.xml \
+ man/sd-daemon.xml
systemd_SOURCES = \
src/main.c
$(XSLTPROC) -o ${@:.in=} --nonet http://docbook.sourceforge.net/release/xsl/current/xhtml-1_1/docbook.xsl $< && \
mv ${@:.in=} $@
+man/%.3: man/%.xml
+ $(XSLTPROC_PROCESS_MAN)
+
+man/%.3.in: man/%.xml.in
+ $(XSLTPROC_PROCESS_MAN)
+
man/%.5: man/%.xml
$(XSLTPROC_PROCESS_MAN)
man/%.7.in: man/%.xml.in
$(XSLTPROC_PROCESS_MAN_IN)
+man/%.8: man/%.xml
+ $(XSLTPROC_PROCESS_MAN)
+
+man/%.8.in: man/%.xml.in
+ $(XSLTPROC_PROCESS_MAN_IN)
+
man/%.html: man/%.xml
$(XSLTPROC_PROCESS_HTML)
--- /dev/null
+<?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-daemon">
+
+ <refentryinfo>
+ <title>sd-daemon</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-daemon</refentrytitle>
+ <manvolnum>7</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd-daemon</refname>
+ <refpurpose>Reference implementation of APIs for
+ new-style daemons</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><filename>sd-daemon.c</filename> and
+ <filename>sd-daemon.h</filename> provide a reference
+ implementation of various APIs for new-style daemons,
+ as implemented by the
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ init system.</para>
+
+ <para>See
+ <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_is_fifo</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for more information about the functions
+ implemented. In addition to these functions a couple
+ of logging prefixes are defined as macros:</para>
+
+ <programlisting>#define SD_EMERG "<0>" /* system is unusable */
+#define SD_ALERT "<1>" /* action must be taken immediately */
+#define SD_CRIT "<2>" /* critical conditions */
+#define SD_ERR "<3>" /* error conditions */
+#define SD_WARNING "<4>" /* warning conditions */
+#define SD_NOTICE "<5>" /* normal but significant condition */
+#define SD_INFO "<6>" /* informational */
+#define SD_DEBUG "<7>" /* debug-level messages */</programlisting>
+
+ <para>These prefixes are intended to be used in
+ conjunction with STDERR-based logging as implemented
+ by systemd. If a systemd service definition file is
+ configured with <varname>StandardError=syslog</varname>
+ or <varname>StandardError=kmsg</varname> these
+ prefixes can be used to encode a log level in lines
+ printed. This is similar to the kernel
+ <function>printk()</function>-style logging. See
+ <citerefentry><refentrytitle>klogctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ for more information.</para>
+
+ <para>The log levels are identical to
+ <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>'s
+ log level system. To use these prefixes simply prefix
+ every line with one of these strings. A line that is
+ not prefixed will be logged at the default log level
+ SD_INFO.</para>
+
+ <example>
+ <title>Hello World</title>
+
+ <para>A daemon may log with the log level
+ NOTICE by issuing this call:</para>
+
+ <programlisting>fprintf(stderr, SD_NOTICE "Hello World!\n");</programlisting>
+ </example>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>These interfaces 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. See the respective function man pages
+ for details.</para>
+
+ <para>In addition, for details about the algorithms
+ 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>These APIs 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, either
+ verbatim or in excerpts. These interfaces are
+ currently not available in a dynamic library.</para>
+
+ <para>The functions directly related to new-style
+ daemons become NOPs when -DDISABLE_SYSTEMD is set
+ during compilation. In addition, if
+ <filename>sd-daemon.c</filename> is compiled on
+ non-Linux systems they become NOPs, too.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_is_fifo</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>,
+ <citerefentry><refentrytitle>fprintf</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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_booted">
+
+ <refentryinfo>
+ <title>sd_booted</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_booted</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_booted</refname>
+ <refpurpose>Test whether the system is running the systemd init system.</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include "sd-daemon.h"</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_booted</function></funcdef>
+ <paramdef>void</paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+ <para><function>sd_booted()</function> checks whether
+ the system was booted up using the systemd init system.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On failure, this call returns a negative
+ errno-style error code. If the system was booted up
+ with systemd as init system this call returns a
+ postive return value, zero otherwise.</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
+ <filename>/cgroup/systemd</filename> virtual file
+ system is mounted, by comparing the st_dev value of
+ the <function>stat()</function> data of
+ <filename>/cgroup</filename> and
+ <filename>/cgroup/systemd</filename>.</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_booted()</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>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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>
--- /dev/null
+<?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>
--- /dev/null
+<?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>
/*
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.
*/
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
- string. The following strings are known:
+ string. The following variables are known:
READY=1 Tells systemd that daemon startup is finished (only
relevant for services of Type=notify). The passed
MAINPID=... The main pid of a daemon, in case systemd did not
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
if systemd could be notified, 0 if it couldn't possibly because
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