'\" t
.\"     Title: udevd
.\"    Author: [see the "Author" section]
.\" Generator: DocBook XSL Stylesheets v1.75.2 <http://docbook.sf.net/>
.\"      Date: 02/10/2011
.\"    Manual: udevd
.\"    Source: udev
.\"  Language: English
.\"
.TH "UDEVD" "8" "02/10/2011" "udev" "udevd"
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
udevd \- event managing daemon
.SH "SYNOPSIS"
.HP \w'\fBudevd\fR\ 'u
\fBudevd\fR [\fB\-\-daemon\fR] [\fB\-\-debug\fR] [\fB\-\-children\-max=\fR] [\fB\-\-exec\-delay=\fR] [\fB\-\-resolve\-names=early|late|never\fR] [\fB\-\-version\fR] [\fB\-\-help\fR]
.SH "DESCRIPTION"
.PP
udevd listens to kernel uevents\&. For every event, udevd executes matching instructions specified in udev rules\&. See
\fBudev\fR(7)\&.
.PP
On startup the content of the directory
/lib/udev/devices
is copied to
/dev\&. If kernel modules specify static device nodes, these nodes are created even without a corresponding kernel device, to allow on\-demand loading of kernel modules\&. Matching permissions specified in udev rules are applied to these static device nodes\&.
.PP
The behavior of the running daemon can be changed with
\fBudevadm control\fR\&.
.SH "OPTIONS"
.PP
\fB\-\-daemon\fR
.RS 4
Detach and run in the background\&.
.RE
.PP
\fB\-\-debug\fR
.RS 4
Print debug messages to stderr\&.
.RE
.PP
\fB\-\-children\-max=\fR
.RS 4
Limit the number of parallel executed events\&.
.RE
.PP
\fB\-\-exec\-delay=\fR
.RS 4
Number of seconds to delay the execution of RUN instructions\&. This might be useful when debugging system crashes during coldplug cause by loading non\-working kernel modules\&.
.RE
.PP
\fB\-\-resolve\-names=\fR
.RS 4
Specify when udevd should resolve names of users and groups\&. When set to
\fBearly\fR
(the default) names will be resolved when the rules are parsed\&. When set to
\fBlate\fR
names will be resolved for every event\&. When set to
\fBnever\fR
names will never be resolved and all devices will be owned by root\&.
.RE
.PP
\fB\-\-version\fR
.RS 4
Print version number\&.
.RE
.PP
\fB\-\-help\fR
.RS 4
Print help text\&.
.RE
.SH "ENVIRONMENT"
.PP
\fIUDEV_LOG=\fR
.RS 4
Set the logging priority\&.
.RE
.SH "KERNEL COMMAND LINE"
.PP
\fIudev\&.log\-priority=\fR
.RS 4
Set the logging priority\&.
.RE
.PP
\fIudev\&.children\-max=\fR
.RS 4
Limit the number of parallel executed events\&.
.RE
.PP
\fIudev\&.exec\-delay=\fR
.RS 4
Number of seconds to delay the execution of RUN instructions\&. This might be useful when debugging system crashes during coldplug cause by loading non\-working kernel modules\&.
.RE
.SH "AUTHOR"
.PP
Written by Kay Sievers
kay\&.sievers@vrfy\&.org\&.
.SH "SEE ALSO"
.PP
\fBudev\fR(7),
\fBudevadm\fR(8)