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diff --git a/src/libudev/udev_device_new_from_syspath.xml b/src/libudev/udev_device_new_from_syspath.xml new file mode 100644 index 0000000000..0bb71c8e91 --- /dev/null +++ b/src/libudev/udev_device_new_from_syspath.xml @@ -0,0 +1,214 @@ +<?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" [ +<!ENTITY % entities SYSTEM "custom-entities.ent" > +%entities; +]> + +<!-- + This file is part of systemd. + + Copyright 2015 David Herrmann <dh.herrmann@gmail.com> + + 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="udev_device_new_from_syspath" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>udev_device_new_from_syspath</title> + <productname>systemd</productname> + + <authorgroup> + <author> + <contrib>Developer</contrib> + <firstname>David</firstname> + <surname>Herrmann</surname> + <email>dh.herrmann@gmail.com</email> + </author> + </authorgroup> + </refentryinfo> + + <refmeta> + <refentrytitle>udev_device_new_from_syspath</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>udev_device_new_from_syspath</refname> + <refname>udev_device_new_from_devnum</refname> + <refname>udev_device_new_from_subsystem_sysname</refname> + <refname>udev_device_new_from_device_id</refname> + <refname>udev_device_new_from_environment</refname> + <refname>udev_device_ref</refname> + <refname>udev_device_unref</refname> + + <refpurpose>Create, acquire and release a udev device object</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <libudev.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_new_from_syspath</function></funcdef> + <paramdef>struct udev *<parameter>udev</parameter></paramdef> + <paramdef>const char *<parameter>syspath</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_new_from_devnum</function></funcdef> + <paramdef>struct udev *<parameter>udev</parameter></paramdef> + <paramdef>char <parameter>type</parameter></paramdef> + <paramdef>dev_t <parameter>devnum</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_new_from_subsystem_sysname</function></funcdef> + <paramdef>struct udev *<parameter>udev</parameter></paramdef> + <paramdef>const char *<parameter>subsystem</parameter></paramdef> + <paramdef>const char *<parameter>sysname</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_new_from_device_id</function></funcdef> + <paramdef>struct udev *<parameter>udev</parameter></paramdef> + <paramdef>const char *<parameter>id</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_new_from_environment</function></funcdef> + <paramdef>struct udev *<parameter>udev</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_ref</function></funcdef> + <paramdef>struct udev_device *<parameter>udev_device</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>struct udev_device *<function>udev_device_unref</function></funcdef> + <paramdef>struct udev_device *<parameter>udev_device</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>udev_device_new_from_syspath</function>, + <function>udev_device_new_from_devnum</function>, + <function>udev_device_new_from_subsystem_sysname</function>, + <function>udev_device_new_from_device_id</function>, and + <function>udev_device_new_from_environment</function> + allocate a new udev device object and returns a pointer to it. This + object is opaque and must not be accessed by the caller via different + means than functions provided by libudev. Initially, the reference count + of the device is 1. You can acquire further references, and drop + gained references via <function>udev_device_ref()</function> and + <function>udev_device_unref()</function>. Once the reference count hits 0, + the device object is destroyed and freed.</para> + + <para><function>udev_device_new_from_syspath</function>, + <function>udev_device_new_from_devnum</function>, + <function>udev_device_new_from_subsystem_sysname</function>, and + <function>udev_device_new_from_device_id</function> + create the device object based on information found in + <filename>/sys</filename>, annotated with properties from the udev-internal + device database. A syspath is any subdirectory of <filename>/sys</filename>, + with the restriction that a subdirectory of <filename>/sys/devices</filename> + (or a symlink to one) represents a real device and as such must contain + a <filename>uevent</filename> file. <function>udev_device_new_from_devnum</function> + takes a device type, which can be <constant>b</constant> for block devices or + <constant>c</constant> for character devices, as well as a devnum (see + <citerefentry project='man-pages'><refentrytitle>makedev</refentrytitle><manvolnum>3</manvolnum></citerefentry>). + <function>udev_device_new_from_subsystem_sysname</function> looks up devices based + on the provided subsystem and sysname + (see <citerefentry><refentrytitle>udev_device_get_subsystem</refentrytitle><manvolnum>3</manvolnum></citerefentry> + and + <citerefentry><refentrytitle>udev_device_get_sysname</refentrytitle><manvolnum>3</manvolnum></citerefentry>) + and <function>udev_device_new_from_device_id</function> looks up devices based on the provided + device ID, which is a special string in one of the following four forms: + <table> + <title>Device ID strings</title> + + <tgroup cols='2'> + <colspec colname='example' /> + <colspec colname='explanation' /> + <thead><row> + <entry>Example</entry> + <entry>Explanation</entry> + </row></thead> + <tbody> + <row><entry><varname>b8:2</varname></entry> + <entry>block device major:minor</entry></row> + + <row><entry><varname>c128:1</varname></entry> + <entry>char device major:minor</entry></row> + + <row><entry><varname>n3</varname></entry> + <entry>network device ifindex</entry></row> + + <row><entry><varname>+sound:card29</varname></entry> + <entry>kernel driver core subsystem:device name</entry></row> + </tbody> + </tgroup> + </table> + </para> + + <para><function>udev_device_new_from_environment</function> + creates a device from the current environment (see + <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>). + Each key-value pair is interpreted in the same way as if it was + received in an uevent (see + <citerefentry><refentrytitle>udev_monitor_receive_device</refentrytitle><manvolnum>3</manvolnum></citerefentry>). + The keys <constant>DEVPATH</constant>, <constant>SUBSYSTEM</constant>, + <constant>ACTION</constant>, and <constant>SEQNUM</constant> are mandatory.</para> + + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On success, <function>udev_device_new_from_syspath()</function>, + <function>udev_device_new_from_devnum()</function>, + <function>udev_device_new_from_subsystem_sysname()</function>, + <function>udev_device_new_from_device_id()</function> and + <function>udev_device_new_from_environment()</function> return a + pointer to the allocated udev device. On failure, + <constant>NULL</constant> is returned, + and <varname>errno</varname> is set appropriately. + <function>udev_device_ref()</function> returns the argument + that it was passed, unmodified. + <function>udev_device_unref()</function> always returns + <constant>NULL</constant>.</para> + </refsect1> + + <refsect1> + <title>See Also</title> + + <para> + <citerefentry><refentrytitle>udev_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>udev_device_get_syspath</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>udev_device_has_tag</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>udev_enumerate_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>udev_monitor_new_from_netlink</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>udev_list_entry</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + </para> + </refsect1> + +</refentry> |