From edf2573743b25273bee020230a60f1a054b8ec60 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>

Date: Thu, 25 Sep 2014 17:27:33 -0400

Subject: [PATCH] man: add sd_event_add_child(3)

---

 Makefile-man.am             |   7 ++

 man/sd_event_add_child.xml  | 205 ++++++++++++++++++++++++++++++++++++++++++++

 man/sd_event_add_signal.xml |   1 +

 man/sd_event_add_time.xml   |   1 +

 4 files changed, 214 insertions(+)

 create mode 100644 man/sd_event_add_child.xml

diff --git a/Makefile-man.am b/Makefile-man.am

index 85a3612f39..53e2f2cf17 100644

--- a/Makefile-man.am

+++ b/Makefile-man.am

@@ -741,6 +741,7 @@ MANPAGES += \

 	man/sd_bus_open_user.3 \

 	man/sd_bus_path_encode.3 \

 	man/sd_bus_request_name.3 \

+	man/sd_event_add_child.3 \

 	man/sd_event_add_signal.3 \

 	man/sd_event_add_time.3 \

 	man/sd_event_new.3 \

@@ -803,6 +804,7 @@ MANPAGES_ALIAS += \

 	man/sd_bus_unref.3 \

 	man/sd_event_default.3 \

 	man/sd_event_ref.3 \

+	man/sd_event_source_get_child_pid.3 \

 	man/sd_event_source_get_signal.3 \

 	man/sd_event_source_get_time.3 \

 	man/sd_event_source_get_time_accuracy.3 \

@@ -867,6 +869,7 @@ man/sd_bus_release_name.3: man/sd_bus_request_name.3

 man/sd_bus_unref.3: man/sd_bus_new.3

 man/sd_event_default.3: man/sd_event_new.3

 man/sd_event_ref.3: man/sd_event_new.3

+man/sd_event_source_get_child_pid.3: man/sd_event_add_child.3

 man/sd_event_source_get_signal.3: man/sd_event_add_signal.3

 man/sd_event_source_get_time.3: man/sd_event_add_time.3

 man/sd_event_source_get_time_accuracy.3: man/sd_event_add_time.3

@@ -1043,6 +1046,9 @@ man/sd_event_default.html: man/sd_event_new.html

 man/sd_event_ref.html: man/sd_event_new.html

 	$(html-alias)

+man/sd_event_source_get_child_pid.html: man/sd_event_add_child.html

+	$(html-alias)

+

 man/sd_event_source_get_signal.html: man/sd_event_add_signal.html

 	$(html-alias)

@@ -1548,6 +1554,7 @@ EXTRA_DIST += \

 	man/sd_bus_open_user.xml \

 	man/sd_bus_path_encode.xml \

 	man/sd_bus_request_name.xml \

+	man/sd_event_add_child.xml \

 	man/sd_event_add_signal.xml \

 	man/sd_event_add_time.xml \

 	man/sd_event_new.xml \

diff --git a/man/sd_event_add_child.xml b/man/sd_event_add_child.xml

new file mode 100644

index 0000000000..a3b4d85ac8

--- /dev/null

+++ b/man/sd_event_add_child.xml

@@ -0,0 +1,205 @@

+ 

+

+"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" conditional="ENABLE_KDBUS">

+

+  <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>

+

+    <refpurpose>Add a child state change event source to an event loop</refpurpose>

+  </refnamediv>

+

+  <refsynopsisdiv>

+    <funcsynopsis>

+      <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>

+

+      <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>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_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

+    state change event source to an event loop object. The event loop

+    is specified in <parameter>event</parameter>, the event source is

+    returned in the <parameter>source</parameter> parameter. The

+    <parameter>pid</parameter> parameter specifies 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>const

+    siginfo_t</structname> structure containing the information about

+    the 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

+    terminating), <constant>WSTOPPED</constant> (watch for the child

+    being stopped by a signal), and <constant>WCONTINUED</constant>

+    (watch for the child being resumed by a signal). See

+    <citerefentry><refentrytitle>waitid</refentrytitle><manvolnum>2</manvolnum></citerefentry>

+    for futher information.</para>

+

+    <para>Only a single handler may be installed for a specific

+    child. 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

+    <constant>SD_EVENT_ON</constant> mode is set.

+    </para>

+

+    <para><function>sd_event_source_get_child_pid()</function>

+    retrieves the configured <parameter>pid</parameter> of a child

+    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 <type>pid_t</type> to return the result 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><varname>-ENOMEM</varname></term>

+

+        <listitem><para>Not enough memory to allocate an object.</para></listitem>

+      </varlistentry>

+

+      <varlistentry>

+        <term><varname>-EINVAL</varname></term>

+

+        <listitem><para>An invalid argument has been passed. This includes

+        specyfing an empty mask in <parameter>options</parameter> or a mask

+        which constains values different than a combination of

+        <constant>WEXITED</constant>, <constant>WSTOPPED</constant>, and

+        <constant>WCONTINUED</constant>.

+        </para></listitem>

+

+      </varlistentry>

+

+      <varlistentry>

+        <term><varname>-EBUSY</varname></term>

+

+        <listitem><para>An handler is already installed for this

+        child.</para></listitem>

+

+      </varlistentry>

+

+      <varlistentry>

+        <term><varname>-ESTALE</varname></term>

+

+        <listitem><para>The event loop is already terminated.</para></listitem>

+

+      </varlistentry>

+

+      <varlistentry>

+        <term><varname>-ECHILD</varname></term>

+

+        <listitem><para>The event loop has been created in a different process.</para></listitem>

+

+      </varlistentry>

+

+    </variablelist>

+  </refsect1>

+

+  <refsect1>

+    <title>Notes</title>

+

+    <para><function>sd_event_add_child()</function> and the other functions

+    described here are available as a shared library, which can be

+    compiled and linked to with the

+    <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>

+    file.</para>

+  </refsect1>

+

+  <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_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>

+    </para>

+  </refsect1>

+

+</refentry>

diff --git a/man/sd_event_add_signal.xml b/man/sd_event_add_signal.xml

index 2344fb3c02..2b656b67a2 100644

--- a/man/sd_event_add_signal.xml

+++ b/man/sd_event_add_signal.xml

@@ -189,6 +189,7 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>.

       <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>

     </para>

   </refsect1>

diff --git a/man/sd_event_add_time.xml b/man/sd_event_add_time.xml

index d3775e5d5f..e64ed8e207 100644

--- a/man/sd_event_add_time.xml

+++ b/man/sd_event_add_time.xml

@@ -249,6 +249,7 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>.

       <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>

     </para>