96 lines
5.1 KiB
Diff
96 lines
5.1 KiB
Diff
|
From bb9c2f82137bb6d1a352341eb81ed2a0ac96d4cb Mon Sep 17 00:00:00 2001
|
||
|
From: Lennart Poettering <lennart@poettering.net>
|
||
|
Date: Wed, 11 Dec 2013 18:38:51 +0100
|
||
|
Subject: [PATCH] man: explain in more detail how SYSTEMD_READY= influences
|
||
|
SYSTEMD_WANTS= in udev rules
|
||
|
|
||
|
https://bugzilla.redhat.com/show_bug.cgi?id=1026860
|
||
|
---
|
||
|
man/systemd.device.xml | 45 +++++++++++++++++++++++++++++++--------------
|
||
|
1 file changed, 31 insertions(+), 14 deletions(-)
|
||
|
|
||
|
diff --git a/man/systemd.device.xml b/man/systemd.device.xml
|
||
|
index 96ebe89..002b647 100644
|
||
|
--- a/man/systemd.device.xml
|
||
|
+++ b/man/systemd.device.xml
|
||
|
@@ -70,12 +70,15 @@
|
||
|
since no device-specific options may be
|
||
|
configured.</para>
|
||
|
|
||
|
- <para>systemd will automatically create dynamic device
|
||
|
- units for all kernel devices that are marked with the
|
||
|
- "systemd" udev tag (by default all block and network
|
||
|
- devices, and a few others). This may be used to define
|
||
|
- dependencies between devices and other
|
||
|
- units.</para>
|
||
|
+ <para>systemd will dynamically create device units for
|
||
|
+ all kernel devices that are marked with the "systemd"
|
||
|
+ udev tag (by default all block and network devices,
|
||
|
+ and a few others). This may be used to define
|
||
|
+ dependencies between devices and other units. To tag a
|
||
|
+ udev device use <literal>TAG+="systemd"</literal> in
|
||
|
+ the udev rules file, see
|
||
|
+ <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
|
+ for details.</para>
|
||
|
|
||
|
<para>Device units are named after the
|
||
|
<filename>/sys</filename> and
|
||
|
@@ -93,7 +96,7 @@
|
||
|
|
||
|
<para>The settings of device units may either be
|
||
|
configured via unit files, or directly from the udev
|
||
|
- database (which is recommended). The following udev
|
||
|
+ database (which is recommended). The following udev device
|
||
|
properties are understood by systemd:</para>
|
||
|
|
||
|
<variablelist class='udev-directives'>
|
||
|
@@ -101,16 +104,26 @@
|
||
|
<term><varname>SYSTEMD_WANTS=</varname></term>
|
||
|
<listitem><para>Adds dependencies of
|
||
|
type <varname>Wants</varname> from
|
||
|
- this unit to all listed units. This
|
||
|
+ the device unit to all listed units. This
|
||
|
may be used to activate arbitrary
|
||
|
- units, when a specific device becomes
|
||
|
+ units when a specific device becomes
|
||
|
available. Note that this and the
|
||
|
other tags are not taken into account
|
||
|
unless the device is tagged with the
|
||
|
<literal>systemd</literal> string in
|
||
|
the udev database, because otherwise
|
||
|
the device is not exposed as systemd
|
||
|
- unit.</para></listitem>
|
||
|
+ unit (see above). Note that systemd
|
||
|
+ will only act on
|
||
|
+ <varname>Wants</varname> dependencies
|
||
|
+ when a device first becomes active, it
|
||
|
+ will not act on them if they are added
|
||
|
+ to devices that are already
|
||
|
+ active. Use
|
||
|
+ <varname>SYSTEMD_READY=</varname> (see
|
||
|
+ below) to influence on which udev
|
||
|
+ event to trigger the device
|
||
|
+ dependencies.</para></listitem>
|
||
|
</varlistentry>
|
||
|
|
||
|
<varlistentry>
|
||
|
@@ -135,10 +148,14 @@
|
||
|
device disappears from the udev
|
||
|
tree. This option is useful to support
|
||
|
devices that initially show up in an
|
||
|
- uninitialized state in the tree, and for
|
||
|
- which a changed event is generated the
|
||
|
- moment they are fully set
|
||
|
- up.</para></listitem>
|
||
|
+ uninitialized state in the tree, and
|
||
|
+ for which a <literal>changed</literal>
|
||
|
+ event is generated the moment they are
|
||
|
+ fully set up. Note that
|
||
|
+ <varname>SYSTEMD_WANTS=</varname> (see
|
||
|
+ above) is not acted on as long as
|
||
|
+ <varname>SYSTEMD_READY=0</varname> is
|
||
|
+ set for a device.</para></listitem>
|
||
|
</varlistentry>
|
||
|
|
||
|
<varlistentry>
|