-<?xml version='1.0'?> <!--*-nxml-*-->
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
<!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.
+ This file is part of elogind.
Copyright 2010 Lennart Poettering
- systemd is free software; you can redistribute it and/or modify it
+ elogind is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
- systemd is distributed in the hope that it will be useful, but
+ elogind 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ along with elogind; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="sd_notify"
<refentryinfo>
<title>sd_notify</title>
- <productname>systemd</productname>
+ <productname>elogind</productname>
<authorgroup>
<author>
<refsynopsisdiv>
<funcsynopsis>
- <funcsynopsisinfo>#include <systemd/sd-daemon.h></funcsynopsisinfo>
+ <funcsynopsisinfo>#include <elogind/sd-daemon.h></funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>sd_notify</function></funcdef>
<para><function>sd_notify()</function> may be called by a service
to notify the service manager about state changes. It can be used
to send arbitrary information, encoded in an
- environment-block-like string. Most importantly it can be used for
+ 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
<term>READY=1</term>
<listitem><para>Tells the service manager that service startup
- is finished. This is only used by systemd if the service
+ is finished. This is only used by elogind if the service
definition file has Type=notify set. Since there is little
value in signaling non-readiness, the only value services
should send is <literal>READY=1</literal> (i.e.
to the service manager that describes the service state. This
is free-form 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
+ percentages and failing programs could pass a human-readable
error message. Example: <literal>STATUS=Completed 66% of file
system check...</literal></para></listitem>
</varlistentry>
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for information how to enable this functionality and
<citerefentry><refentrytitle>sd_watchdog_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- for the details of how the service can check if the the
+ for the details of how the service can check whether the
watchdog is enabled. </para></listitem>
</varlistentry>
<varlistentry>
<term>FDSTORE=1</term>
- <listitem><para>Stores additional file descriptors in the
- service manager. File descriptors sent this way will be
- maintained per-service by the service manager and be passed
- again using the usual file descriptor passing logic on the
- next invocation of the service (see
- <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>).
- This is useful for implementing service restart schemes where
- services serialize their state to <filename>/run</filename>,
- push their file descriptors to the system manager, and are
- then restarted, retrieving their state again via socket
- passing and <filename>/run</filename>. Note that the service
- manager will accept messages for a service only if
- <varname>FileDescriptorStoreMax=</varname> is set to non-zero
- for it (defaults to zero). See
- <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for details. Multiple arrays of file descriptors may be sent
- in separate messages, in which case the arrays are combined.
- Note that the service manager removes duplicate file
- descriptors before passing them to the service. Use
- <function>sd_pid_notify_with_fds()</function> to send messages
- with <literal>FDSTORE=1</literal>, see
- below.</para></listitem>
+ <listitem><para>Stores additional file descriptors in the service manager. File
+ descriptors sent this way will be maintained per-service by the service manager
+ and will be passed again using the usual file descriptor passing logic on the next
+ invocation of the service, see
+ <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+ This is useful for implementing service restart schemes where services serialize
+ their state to <filename>/run</filename>, push their file descriptors to the
+ system manager, and are then restarted, retrieving their state again via socket
+ passing and <filename>/run</filename>. Note that the service manager will accept
+ messages for a service only if <varname>FileDescriptorStoreMax=</varname> is set
+ to non-zero for it (defaults to zero, see
+ <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
+ File descriptors must be pollable, see
+ <citerefentry><refentrytitle>epoll_ctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>.
+ Multiple arrays of file descriptors may be sent in separate messages, in which
+ case the arrays are combined. Note that the service manager removes duplicate
+ file descriptors before passing them to the service. Use
+ <function>sd_pid_notify_with_fds()</function> to send messages with
+ <literal>FDSTORE=1</literal>, see below.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>FDNAME=...</term>
+
+ <listitem><para>When used in combination with
+ <varname>FDSTORE=1</varname>, specifies a name for the
+ submitted file descriptors. This name is passed to the service
+ during activation, and may be queried using
+ <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>. File
+ descriptors submitted without this field set, will implicitly
+ get the name <literal>stored</literal> assigned. Note that, if
+ multiple file descriptors are submitted at once, the specified
+ name will be assigned to all of them. In order to assign
+ different names to submitted file descriptors, submit them in
+ separate invocations of
+ <function>sd_pid_notify_with_fds()</function>. The name may
+ consist of any ASCII character, but must not contain control
+ characters or <literal>:</literal>. It may not be longer than
+ 255 characters. If a submitted name does not follow these
+ restrictions, it is ignored.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>WATCHDOG_USEC=...</term>
+
+ <listitem><para>Reset <varname>watchdog_usec</varname> value during runtime.
+ Notice that this is not available when using <function>sd_event_set_watchdog()</function>
+ or <function>sd_watchdog_enabled()</function>.
+ Example : <literal>WATCHDOG_USEC=20000000</literal></para></listitem>
</varlistentry>
</variablelist>
listed above with <varname>X_</varname> to avoid namespace
clashes.</para>
- <para>Note that systemd will accept status data sent from a
+ <para>Note that elogind will accept status data sent from a
service 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>
use as originating PID for the message as first argument. This is
useful to send notification messages on behalf of other processes,
provided the appropriate privileges are available. If the PID
- argument is specified as 0 the process ID of the calling process
+ argument is specified as 0, the process ID of the calling process
is used, in which case the calls are fully equivalent to
<function>sd_notify()</function> and
<function>sd_notifyf()</function>.</para>
<refsect1>
<title>Notes</title>
- <xi:include href="libsystemd-pkgconfig.xml" xpointer="pkgconfig-text"/>
+ <xi:include href="libelogind-pkgconfig.xml" xpointer="pkgconfig-text"/>
- <para>Internally, these functions send a single datagram with the
+ <para>These functions send a single datagram with the
state string as payload to the <constant>AF_UNIX</constant> socket
referenced in the <varname>$NOTIFY_SOCKET</varname> environment
variable. If the first character of
<para>To store an open file descriptor in the service manager,
in order to continue operation after a service restart without
- losing state use <literal>FDSTORE=1</literal>:</para>
+ losing state, use <literal>FDSTORE=1</literal>:</para>
- <programlisting>sd_pid_notify_with_fds(0, 0, "FDSTORE=1", &fd, 1);</programlisting>
+ <programlisting>sd_pid_notify_with_fds(0, 0, "FDSTORE=1\nFDNAME=foobar", &fd, 1);</programlisting>
</example>
</refsect1>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_watchdog_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_watchdog_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff