<manvolnum>8</manvolnum></citerefentry>, receives device uevents directly from
the kernel whenever a device is added or removed from the system, or it changes its
state. When udev receives a device event, it matches its configured set of rules
- against various device attributes to identify the device. Rules that match, may
- provide additional device information to be stored in the udev database, or information
+ against various device attributes to identify the device. Rules that match may
+ provide additional device information to be stored in the udev database or
to be used to create meaningful symlink names.</para>
- <para>All device information udev processes, is stored in the udev database and
+ <para>All device information udev processes is stored in the udev database and
sent out to possible event subscribers. Access to all stored data and the event
- sources are provided by the library libudev.</para>
+ sources is provided by the library libudev.</para>
</refsect1>
<refsect1><title>Configuration</title>
<para>udev configuration files are placed in <filename>/etc/udev/</filename>
- and <filename>/lib/udev/</filename>. All empty lines, or lines beginning with
- '#' will be ignored.</para>
+ and <filename>/lib/udev/</filename>. All empty lines or lines beginning with
+ '#' are ignored.</para>
<refsect2><title>Configuration file</title>
<para>udev expects its main configuration file at <filename>/etc/udev/udev.conf</filename>.
<varlistentry>
<term><option>=</option></term>
<listitem>
- <para>Assign a value to a key. Keys that represent a list, are reset
+ <para>Assign a value to a key. Keys that represent a list are reset
and only this single value is assigned.</para>
</listitem>
</varlistentry>
and removes the node before udev even receives any event. Changing
the node name from the kernel's default creates inconsistencies
and is not supported. If the kernel and NAME specify different names,
- an error will be logged. Udev is only expected to handle device node
+ an error is logged. Udev is only expected to handle device node
permissions and to create additional symlinks, not to change
kernel-provided device node names. Instead of renaming a device node,
SYMLINK should be used. Symlink names must never conflict with
- device node names, it will result in unpredictable behavior.</para>
+ device node names, it results in unpredictable behavior.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>SYMLINK</option></term>
<listitem>
- <para>The name of a symlink targeting the node. Every matching rule will add
+ <para>The name of a symlink targeting the node. Every matching rule adds
this value to the list of symlinks to be created. Multiple symlinks may be
specified by separating the names by the space character. In case multiple
- devices claim the same name, the link will always point to the device with
- the highest link_priority. If the current device goes away, the links will
- be re-evaluated and the device with the next highest link_priority will own
+ devices claim the same name, the link always points to the device with
+ the highest link_priority. If the current device goes away, the links are
+ re-evaluated and the device with the next highest link_priority becomes the owner of
the link. If no link_priority is specified, the order of the devices, and
- which one of them will own the link, is undefined. Claiming the same name for
+ which one of them owns the link, is undefined. Claiming the same name for
a symlink, which is or might be used for a device node, may result in
unexpected behavior and is not supported.
</para>
<term><option>cmdline</option></term>
<listitem>
<para>Import a single property from the kernel commandline. For simple flags
- the value of the property will be set to '1'.</para>
+ the value of the property is set to '1'.</para>
</listitem>
</varlistentry>
<varlistentry>
</listitem>
</varlistentry>
</variablelist>
- <para>If no option is given, udev will choose between <option>program</option>
+ <para>If no option is given, udev chooses between <option>program</option>
and <option>file</option> based on the executable bit of the file
permissions.</para>
</listitem>
<varlistentry>
<term><option>event_timeout=</option></term>
<listitem>
- <para>Number of seconds an event will wait for operations to finish, before it
- will terminate itself.</para>
+ <para>Number of seconds an event waits for operations to finish before
+ giving up and terminating itself.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>static_node=</option></term>
<listitem>
<para>Apply the permissions specified in this rule to a static device node with
- the specified name. Static device nodes might be provided by kernel modules,
+ the specified name. Static device nodes might be provided by kernel modules
or copied from <filename>/lib/udev/devices</filename>. These nodes might not have
- a corresponding kernel device at the time udevd is started, and allow to trigger
- automatic kernel module on-demand loading.</para>
+ a corresponding kernel device at the time udevd is started; they can trigger
+ automatic kernel module loading.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>watch</option></term>
<listitem>
<para>Watch the device node with inotify, when closed after being opened for
- writing, a change uevent will be synthesised.</para>
+ writing, a change uevent is synthesised.</para>
</listitem>
</varlistentry>
<varlistentry>
<varlistentry>
<term><option>$attr{<replaceable>file</replaceable>}</option>, <option>%s{<replaceable>file</replaceable>}</option></term>
<listitem>
- <para>The value of a sysfs attribute found at the device, where
+ <para>The value of a sysfs attribute found at the device where
all keys of the rule have matched. If the matching device does not have
such an attribute, and a previous KERNELS, SUBSYSTEMS, DRIVERS, or
ATTRS test selected a parent device, use the attribute from that
~ianmdlvl / elogind.git / blobdiff