diff options
Diffstat (limited to 'udev.8')
| -rw-r--r-- | udev.8 | 51 |
1 files changed, 38 insertions, 13 deletions
@@ -2,28 +2,30 @@ .SH NAME udev \- Linux configurable dynamic device naming support .SH SYNOPSIS -.B udev +.BI udev " hotplug-subsystem" .SH "DESCRIPTION" .B udev creates or removes device node files usually located in the /dev directory. +Its goal is to provide a dynamic device directory that contains only the files +for devices that are actually present. +.P As part of the .B hotplug subsystem, .B udev -is exectuted if a kernel device is added or removed from the system. -.P +is executed if a kernel device is added or removed from the system. On device creation, .B udev -reads the sysfs directory of the given device, to collect device attributes +reads the sysfs directory of the given device to collect device attributes like label, serial number or bus device number. These attributes are passed as a key to the namedev subsystem to receive a unique name for device file creation. namedev maintains a database for devices present on the system. -.P +.br On device removal, .B udev -queries the namedev database for the name of the device file to delete. -.P +queries the namedev database for the name of the device file to be deleted. +.SH "CONFIGURATION" namedev expects its configuration at .I /etc/udev/namedev.config. The file consists of a set of lines. All empty lines and @@ -31,11 +33,16 @@ lines beginning with a '#' will be ignored. .br Every line defines the mapping between device attributes and the device file name. It starts with a keyword defining the method used to match, followed by -one ore more keys to compare, optional ownwership and permission settings and -the filename for the device. If no matching configuration is found, -the default kernel device name is used. +one ore more keys to compare and the filename for the device. If no matching +configuration is found, the default kernel device name is used. .P -.I method, key,[key,...] [owner,] [group,] [mode,] name +The line format is: +.RS +.sp +.I method, key,[key,...] name +.sp +.RE +where valid methods with corresponding keys are: .TP .B LABEL device label or serial number, like USB serial number, SCSI UUID or @@ -62,7 +69,9 @@ key: \fBKERNEL_NAME\fP calling external program, that returns a string to match .br keys: \fBBUS\fP, \fBPROGRAM\fP, \fBID\fP -.SH "EXAMPLE" +.P +A sample \fInamedev.conf\fP might look like this: +.sp .nf # USB printer to be called lp_color LABEL, BUS="usb", serial="W09090207101241330", NAME="lp_color" @@ -79,6 +88,22 @@ REPLACE, KERNEL="ttyUSB1", NAME="pda" # if /sbin/dev_id returns "V0815" device will be called dev0815 CALLOUT, PROGRAM="/sbin/dev_id", BUS="pci", ID="V0815", NAME="dev0815" .fi +.P +Permissions and ownership for the created device files may specified at +.I /etc/udev/namedev.permissions. +The file consists of a set of lines. All empty lines and +lines beginning with a '#' will be ignored. +.br +Every line lists a device name followed by owner, group and permission mode. All values are separated by colons. +.sp +A sample \fInamedev.permissions\fP might look like this: +.sp +.nf +#name:user:group:mode +ttyUSB1:root:uucp:0666 +dsp1:::0666 +.fi + .SH "FILES" .nf .ft B @@ -89,7 +114,7 @@ CALLOUT, PROGRAM="/sbin/dev_id", BUS="pci", ID="V0815", NAME="dev0815" .fi .LP .SH "SEE ALSO" -.B hotplug (8) +.BR hotplug (8) .PP The .I http://linux-hotplug.sourceforge.net/ |