daandemeyer / rpms / systemd

Forked from rpms/systemd 2 years ago
Clone
65878a
From f0f727fbb8576afc7ea31f2b6aacccdd565472d0 Mon Sep 17 00:00:00 2001
65878a
From: Lennart Poettering <lennart@poettering.net>
65878a
Date: Wed, 11 Dec 2013 18:38:51 +0100
65878a
Subject: [PATCH] man: explain in more detail how SYSTEMD_READY= influences
65878a
 SYSTEMD_WANTS= in udev rules
65878a
65878a
https://bugzilla.redhat.com/show_bug.cgi?id=1026860
65878a
---
65878a
 man/systemd.device.xml | 45 +++++++++++++++++++++++++++++++--------------
65878a
 1 file changed, 31 insertions(+), 14 deletions(-)
65878a
65878a
diff --git a/man/systemd.device.xml b/man/systemd.device.xml
65878a
index 96ebe89..002b647 100644
65878a
--- a/man/systemd.device.xml
65878a
+++ b/man/systemd.device.xml
65878a
@@ -70,12 +70,15 @@
65878a
                 since no device-specific options may be
65878a
                 configured.</para>
65878a
 
65878a
-                <para>systemd will automatically create dynamic device
65878a
-                units for all kernel devices that are marked with the
65878a
-                "systemd" udev tag (by default all block and network
65878a
-                devices, and a few others). This may be used to define
65878a
-                dependencies between devices and other
65878a
-                units.</para>
65878a
+                <para>systemd will dynamically create device units for
65878a
+                all kernel devices that are marked with the "systemd"
65878a
+                udev tag (by default all block and network devices,
65878a
+                and a few others). This may be used to define
65878a
+                dependencies between devices and other units. To tag a
65878a
+                udev device use <literal>TAG+="systemd"</literal> in
65878a
+                the udev rules file, see
65878a
+                <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
65878a
+                for details.</para>
65878a
 
65878a
                 <para>Device units are named after the
65878a
                 <filename>/sys</filename> and
65878a
@@ -93,7 +96,7 @@
65878a
 
65878a
                 <para>The settings of device units may either be
65878a
                 configured via unit files, or directly from the udev
65878a
-                database (which is recommended). The following udev
65878a
+                database (which is recommended). The following udev device
65878a
                 properties are understood by systemd:</para>
65878a
 
65878a
                 <variablelist class='udev-directives'>
65878a
@@ -101,16 +104,26 @@
65878a
                                 <term><varname>SYSTEMD_WANTS=</varname></term>
65878a
                                 <listitem><para>Adds dependencies of
65878a
                                 type <varname>Wants</varname> from
65878a
-                                this unit to all listed units. This
65878a
+                                the device unit to all listed units. This
65878a
                                 may be used to activate arbitrary
65878a
-                                units, when a specific device becomes
65878a
+                                units when a specific device becomes
65878a
                                 available. Note that this and the
65878a
                                 other tags are not taken into account
65878a
                                 unless the device is tagged with the
65878a
                                 <literal>systemd</literal> string in
65878a
                                 the udev database, because otherwise
65878a
                                 the device is not exposed as systemd
65878a
-                                unit.</para></listitem>
65878a
+                                unit (see above). Note that systemd
65878a
+                                will only act on
65878a
+                                <varname>Wants</varname> dependencies
65878a
+                                when a device first becomes active, it
65878a
+                                will not act on them if they are added
65878a
+                                to devices that are already
65878a
+                                active. Use
65878a
+                                <varname>SYSTEMD_READY=</varname> (see
65878a
+                                below) to influence on which udev
65878a
+                                event to trigger the device
65878a
+                                dependencies.</para></listitem>
65878a
                         </varlistentry>
65878a
 
65878a
                         <varlistentry>
65878a
@@ -135,10 +148,14 @@
65878a
                                 device disappears from the udev
65878a
                                 tree. This option is useful to support
65878a
                                 devices that initially show up in an
65878a
-                                uninitialized state in the tree, and for
65878a
-                                which a changed event is generated the
65878a
-                                moment they are fully set
65878a
-                                up.</para></listitem>
65878a
+                                uninitialized state in the tree, and
65878a
+                                for which a <literal>changed</literal>
65878a
+                                event is generated the moment they are
65878a
+                                fully set up. Note that
65878a
+                                <varname>SYSTEMD_WANTS=</varname> (see
65878a
+                                above) is not acted on as long as
65878a
+                                <varname>SYSTEMD_READY=0</varname> is
65878a
+                                set for a device.</para></listitem>
65878a
                         </varlistentry>
65878a
 
65878a
                         <varlistentry>