.\" Title: udev
.\" Author:
-.\" Generator: DocBook XSL Stylesheets v1.73.1 <http://docbook.sf.net/>
+.\" Generator: DocBook XSL Stylesheets v1.73.2 <http://docbook.sf.net/>
.\" Date: August 2005
.\" Manual: udev
.\" Source: udev
If udev receives a device event, it matches its configured rules against the available device attributes provided in sysfs to identify the device\. Rules that match may provide additional device information or specify a device node name and multiple symlink names and instruct udev to run additional programs as part of the device event handling\.
.SH "CONFIGURATION"
.PP
-All udev configuration files are placed in
-\fI/etc/udev/*\fR\. Every file consists of a set of lines of text\. All empty lines or lines beginning with \'#\' will be ignored\.
+udev configuration files are placed in
+\fI/etc/udev/\fR
+and
+\fI/lib/udev/\fR\. All empty lines, or lines beginning with \'#\' will be ignored\.
.SS "Configuration file"
.PP
udev expects its main configuration file at
\fI/dev\fR\.
.RE
.PP
-\fBudev_rules\fR
-.RS 4
-The name of the udev rules file or directory to look for files with the suffix
-\fI\.rules\fR\. Multiple rule files are read in lexical order\. The default value is
-\fI/etc/udev/rules\.d\fR\.
-.RE
-.PP
\fBudev_log\fR
.RS 4
The logging priority\. Valid values are the numerical syslog priorities or their textual representations:
.RE
.SS "Rules files"
.PP
-The udev rules are read from the files located in the
-\fI/etc/udev/rules\.d\fR
-directory or at the location specified value in the configuration file\. Every line in the rules file contains at least one key value pair\. There are two kind of keys, match and assignment keys\. If all match keys are matching against its value, the rule gets applied and the assign keys get the specified value assigned\.
+The udev rules are read from the files located in the default rules directory
+\fI/lib/udev/rules\.d/\fR, the custom rules directory
+\fI/etc/udev/rules\.d/\fR
+and the temporary rules directory
+\fI/dev/\.udev/rules\.d/\fR\. All rule files are sorted and processed in lexical order, regardless in which of these directories they live\. Every line in the rules file contains at least one key value pair\. There are two kind of keys, match and assignment keys\. If all match keys are matching against its value, the rule gets applied and the assign keys get the specified value assigned\.
.PP
A matching rule may specify the name of the device node, add a symlink pointing to the node, or run a specified program as part of the event handling\. If no matching rule is found, the default device node name is used\.
.PP
Match the name of the event device\.
.RE
.PP
+\fBNAME\fR
+.RS 4
+Match the name of the node or network interface\. It can be used once the NAME key has been set in one of the preceding rules\.
+.RE
+.PP
\fBSUBSYSTEM\fR
.RS 4
Match the subsystem of the event device\.
\fBRUN\fR
.RS 4
Add a program to the list of programs to be executed for a specific device\. This can only be used for very short running tasks\. Running an event process for a long period of time may block all further events for this or a dependent device\. Long running tasks need to be immediately detached from the event process itself\.
+.sp
+If the specifiefd string starts with
+\fBsocket:\fR\fB\fIpath\fR\fR, all current event values will be passed to the specified socket, as a message in the same format the kernel sends an uevent\. If the first character of the specified path is an @ character, an abstract namespace socket is used, instead of an existing socket file\.
.RE
.PP
\fBLABEL\fR
based on the executable bit of the file permissions\.
.RE
.PP
-\fBWAIT_FOR_SYSFS\fR
+\fBWAIT_FOR\fR
.RS 4
-Wait for the specified sysfs file of the device to be created\. Can be used to fight against kernel sysfs timing issues\.
+Wait for a file to become available\.
.RE
.PP
\fBOPTIONS\fR
.PP
\fBlink_priority=\fR\fB\fIvalue\fR\fR
.RS 4
-Specify the priority of the created symlinks\. Devices with higher priorities overwrite existing symlinks of other devices\.
+Specify the priority of the created symlinks\. Devices with higher priorities overwrite existing symlinks of other devices\. The default is 0\.
.RE
.PP
\fBall_partitions\fR
Create the device nodes for all available partitions of a block device\. This may be useful for removable media devices where media changes are not detected\.
.RE
.PP
+\fBevent_timeout=\fR
+.RS 4
+Number of seconds an event will wait for operations to finish, before it will terminate itself\.
+.RE
+.PP
\fBstring_escape=\fR\fB\fInone|replace\fR\fR
.RS 4
Usually control and other possibly unsafe characters are replaced in strings used for device naming\. The mode of replacement can be specified with this option\.
\fBSYMLINK\fR,
\fBPROGRAM\fR,
\fBOWNER\fR,
-\fBGROUP\fR
+\fBGROUP\fR,
+\fBMODE\fR
and
\fBRUN\fR
fields support simple printf\-like string substitutions\. The
.PP
\fB$attr{\fR\fB\fIfile\fR\fR\fB}\fR, \fB%s{\fR\fB\fIfile\fR\fR\fB}\fR
.RS 4
-The value of a sysfs attribute found at the device, where all keys of the rule have matched\. If the matching device does not have such an attribute, all devices along the chain of parents are searched for a matching attribute\. If the attribute is a symlink, the last element of the symlink target is returned as the value\.
+The value of a sysfs attribute found at the device, where all keys of the rule have matched\. If the matching device does not have such an attribute, follow the chain of parent devices and use the value of the first attribute that matches\. If the attribute is a symlink, the last element of the symlink target is returned as the value\.
.RE
.PP
\fB$env{\fR\fB\fIkey\fR\fR\fB}\fR, \fB%E{\fR\fB\fIkey\fR\fR\fB}\fR
.PP
\fB$name\fR
.RS 4
-The name of the device node\. The value is only set if an earlier rule assigned a value, or during a remove events\.
+The current name of the device node\. If not changed by a rule, it is the name of the kernel device\.
+.RE
+.PP
+\fB$links\fR
+.RS 4
+The current list of symlinks, separated by a space character\. The value is only set if an earlier rule assigned a value, or during a remove events\.
.RE
.PP
\fB$root\fR, \fB%r\fR
Written by Greg Kroah\-Hartman
<greg@kroah\.com>
and Kay Sievers
-<kay\.sievers@vrfy\.org>\. With much help from Dan Stekloff
-<dsteklof@us\.ibm\.com>
-and many others\.
+<kay\.sievers@vrfy\.org>\. With much help from Dan Stekloff and many others\.
.SH "SEE ALSO"
.PP
\fBudevd\fR(8),
~ianmdlvl / elogind.git / blobdiff