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diff --git a/man/sd_event_add_child.xml b/man/sd_event_add_child.xml deleted file mode 100644 index bc732db7fa..0000000000 --- a/man/sd_event_add_child.xml +++ /dev/null @@ -1,246 +0,0 @@ -<?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. - - Copyright 2014 Zbigniew Jędrzejewski-Szmek - - systemd 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 - 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/>. ---> - -<refentry id="sd_event_add_child" xmlns:xi="http://www.w3.org/2001/XInclude"> - - <refentryinfo> - <title>sd_event_add_child</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>More text</contrib> - <firstname>Zbigniew</firstname> - <surname>Jędrzejewski-Szmek</surname> - <email>zbyszek@in.waw.pl</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>sd_event_add_child</refentrytitle> - <manvolnum>3</manvolnum> - </refmeta> - - <refnamediv> - <refname>sd_event_add_child</refname> - <refname>sd_event_source_get_child_pid</refname> - <refname>sd_event_child_handler_t</refname> - - <refpurpose>Add a child process state change event source to an event loop</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <systemd/sd-event.h></funcsynopsisinfo> - - <funcsynopsisinfo><token>typedef</token> struct sd_event_source sd_event_source;</funcsynopsisinfo> - - <funcprototype> - <funcdef>typedef int (*<function>sd_event_child_handler_t</function>)</funcdef> - <paramdef>sd_event_source *<parameter>s</parameter></paramdef> - <paramdef>const siginfo_t *<parameter>si</parameter></paramdef> - <paramdef>void *<parameter>userdata</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_add_child</function></funcdef> - <paramdef>sd_event *<parameter>event</parameter></paramdef> - <paramdef>sd_event_source **<parameter>source</parameter></paramdef> - <paramdef>pid_t <parameter>pid</parameter></paramdef> - <paramdef>int <parameter>options</parameter></paramdef> - <paramdef>sd_event_child_handler_t <parameter>handler</parameter></paramdef> - <paramdef>void *<parameter>userdata</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_get_child_pid</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>pid_t *<parameter>pid</parameter></paramdef> - </funcprototype> - - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para><function>sd_event_add_child()</function> adds a new child - process state change event source to an event loop. The event loop - object is specified in the <parameter>event</parameter> parameter, - the event source object is returned in the - <parameter>source</parameter> parameter. The - <parameter>pid</parameter> parameter specifies the PID of the - process to watch. The <parameter>handler</parameter> must - reference a function to call when the process changes state. The - handler function will be passed the - <parameter>userdata</parameter> pointer, which may be chosen - freely by the caller. The handler also receives a pointer to a - <structname>siginfo_t</structname> structure containing - information about the child process event. The - <parameter>options</parameter> parameter determines which state - changes will be watched for. It must contain an OR-ed mask of - <constant>WEXITED</constant> (watch for the child process - terminating), <constant>WSTOPPED</constant> (watch for the child - process being stopped by a signal), and - <constant>WCONTINUED</constant> (watch for the child process being - resumed by a signal). See <citerefentry - project='man-pages'><refentrytitle>waitid</refentrytitle><manvolnum>2</manvolnum></citerefentry> - for further information.</para> - - <para>Only a single handler may be installed for a specific - child process. The handler is enabled for a single event - (<constant>SD_EVENT_ONESHOT</constant>), but this may be changed - with - <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>. - If the handler function returns a negative error code, it will be - disabled after the invocation, even if the - <constant>SD_EVENT_ON</constant> mode was requested before. - </para> - - <para>To destroy an event source object use - <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - but note that the event source is only removed from the event loop - when all references to the event source are dropped. To make sure - an event source does not fire anymore, even when there's still a - reference to it kept, consider setting the event source to - <constant>SD_EVENT_OFF</constant> with - <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> - - <para>If the second parameter of - <function>sd_event_add_child()</function> is passed as NULL no - reference to the event source object is returned. In this case the - event source is considered "floating", and will be destroyed - implicitly when the event loop itself is destroyed.</para> - - <para>Note that the <parameter>handler</parameter> function is - invoked at a time where the child process is not reaped yet (and - thus still is exposed as a zombie process by the kernel). However, - the child will be reaped automatically after the function - returns. Child processes for which no child process state change - event sources are installed will not be reaped by the event loop - implementation.</para> - - <para>If both a child process state change event source and a - <constant>SIGCHLD</constant> signal event source is installed in - the same event loop, the configured event source priorities decide - which event source is dispatched first. If the signal handler is - processed first, it should leave the child processes for which - child process state change event sources are installed unreaped.</para> - - <para><function>sd_event_source_get_child_pid()</function> - retrieves the configured PID of a child process state change event - source created previously with - <function>sd_event_add_child()</function>. It takes the event - source object as the <parameter>source</parameter> parameter and a - pointer to a <type>pid_t</type> variable to return the process ID - in. - </para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para>On success, these functions return 0 or a positive - integer. On failure, they return a negative errno-style error - code.</para> - </refsect1> - - <refsect1> - <title>Errors</title> - - <para>Returned errors may indicate the following problems:</para> - - <variablelist> - <varlistentry> - <term><constant>-ENOMEM</constant></term> - - <listitem><para>Not enough memory to allocate an object.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>-EINVAL</constant></term> - - <listitem><para>An invalid argument has been passed. This includes - specifying an empty mask in <parameter>options</parameter> or a mask - which contains values different than a combination of - <constant>WEXITED</constant>, <constant>WSTOPPED</constant>, and - <constant>WCONTINUED</constant>. - </para></listitem> - - </varlistentry> - - <varlistentry> - <term><constant>-EBUSY</constant></term> - - <listitem><para>A handler is already installed for this - child process.</para></listitem> - - </varlistentry> - - <varlistentry> - <term><constant>-ESTALE</constant></term> - - <listitem><para>The event loop is already terminated.</para></listitem> - - </varlistentry> - - <varlistentry> - <term><constant>-ECHILD</constant></term> - - <listitem><para>The event loop has been created in a different process.</para></listitem> - - </varlistentry> - - <varlistentry> - <term><constant>-EDOM</constant></term> - - <listitem><para>The passed event source is not a child process event source.</para></listitem> - </varlistentry> - - </variablelist> - </refsect1> - - <xi:include href="libsystemd-pkgconfig.xml" /> - - <refsect1> - <title>See Also</title> - - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_event_source_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>waitid</refentrytitle><manvolnum>2</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |