[PATCH] Makefile tweaks for the DBUS build.

[elogind.git] / udev.8

diff --git a/udev.8 b/udev.8
index 771ecfa454915c2fd3b4eb13478837ff853923f9..0c461967d2444f6bfc9093f6c804d2c10b5ecaad 100644 (file)
--- a/udev.8
+++ b/udev.8
@@ -2,81 +2,243 @@
 .SH NAME
 udev \- Linux configurable dynamic device naming support
 .SH SYNOPSIS
 .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.
 .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
 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
 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.
 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
+These attributes are treated as a key 
+to determine a unique name for device file creation.
+.B udev
+maintains a database for devices present on the system.
+.br

 On device removal,
 .B udev
 On device removal,
 .B udev

-queries the namedev database for the name of the device file to delete.
+queries the internal database for the name of the device file to be deleted.
+.SH "CONFIGURATION"
+All
+.B udev
+configuration files consist of a set of lines of text.  All empty
+lines, and lines beginning with a '#' will be ignored.
+.P
+
+.B udev
+expects its main configuration file at
+.I /etc/udev/udev.conf.
+The file consists of a set of variables and values that allow the user to
+override default udev values.  The current set of variables that can be
+overridden in this file is:
+.TP
+.B udev_root
+This is the where in the filesystem to place the device nodes.  The default
+value for this is
+.I /udev/
+.TP
+.B udev_db
+The name and location of the udev database.  The default value for this is
+.I /udev/.udev.tdb
+.TP
+.B udev_rules
+This is the location of the udev rules file.  The default value for this is
+.I /etc/udev/udev.rules
+.TP
+.B udev_permissions
+This is the location of the udev permission file.  The default value for this is
+.I /etc/udev/udev.permissions
+.TP
+.B default_mode
+This is the default mode for all nodes that have no explicit match in the
+permissions file.  The default value for this is
+.I 0666
+.br
+.P
+.RI "A sample " udev.conf " might look like this:
+.sp
+.nf
+# udev_root - where in the filesystem to place the device nodes
+udev_root="/udev/"
+
+# udev_db - The name and location of the udev database.
+udev_db="/udev/.udev.tdb"
+
+# udev_rules - The name and location of the udev rules file
+udev_rules="/etc/udev/udev.rules"
+
+# udev_permissions - The name and location of the udev permission file
+udev_permissions="/etc/udev/udev.permissions"
+
+# default_mode - set the default mode for all nodes that have no 
+#                explicit match in the permissions file
+default_mode="0666"
+.fi
+.P
+The rules for udev to use when naming devices may specified at
+.I /etc/udev/udev.rules
+or specified by the
+.I udev_rules
+value in the 
+.I /etc/udev/udev.conf
+file.
+.P
+Every line in the rules file define 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 and the filename for the
+device. Optional the name for a symlink targeting the node may specified.
+.br
+If no matching configuration is found, the default kernel device name
+is used.

 .P
 .P

-namedev expects its configuration at
-.I /etc/udev/namedev.config.
-The file consists of a set of lines. All empty lines and
-lines beginning with a '#' will be ignored.
+The line format is:
+.sp
+.I method, key,[key,...] name [, symlink]
+.sp
+where valid methods with corresponding keys are:
+.TP
+.B CALLOUT
+calling external program, that returns a string to match

 .br
 .br

-Every line defines the mapping between device attributes and the name of
-the device file. It starts with a keyword defining the method for
-overriding the default kernel naming scheme, followed by a list
-of keys and ends with the definition of the filename for the device.
+.RB "keys: " BUS ", " PROGRAM ", " ID

 .TP
 .B LABEL
 device label or serial number, like USB serial number, SCSI UUID or
 file system label
 .TP
 .B LABEL
 device label or serial number, like USB serial number, SCSI UUID or
 file system label

+.br
+.RB "keys: " BUS ", "
+.I sysfs_attribute

 .TP
 .B NUMBER
 device number on the bus, like PCI bus id
 .TP
 .B NUMBER
 device number on the bus, like PCI bus id

+.br
+.RB "keys: " BUS ", " ID

 .TP
 .B TOPOLOGY
 device position on bus, like physical port of USB device
 .TP
 .B TOPOLOGY
 device position on bus, like physical port of USB device

+.br
+.RB "keys: " BUS ", " PLACE

 .TP
 .B REPLACE
 string replacement of the kernel device name
 .TP
 .B REPLACE
 string replacement of the kernel device name

+.br
+.RB "key: " KERNEL_NAME
+.P
+The methods are applied in the following order:
+.BR CALLOUT ", " LABEL ", " NUMBER ", " TOPOLOGY ", " REPLACE "."
+.P
+.RB "The " NAME " ," SYMLINK " and " PROGRAM
+fields support simple printf-like string substitution:
+.TP
+.B %n
+The "kernel number" of the device.
+for example, 'sda3' has a "kernel number" of '3'
+.TP
+.B %M
+The kernel major number for the device.
+.TP
+.B %m
+The kernel minor number for the device.
+.TP
+.B %b
+The bus id for the device.
+.TP
+.B %c
+The CALLOUT program returned string.
+(This does not work within the PROGRAM field for the obvious reason.)
+.TP
+.B %D
+Use the devfs style disk name for this device.
+For partitions, this will result in 'part%n'
+If this is not a partition, it will result in 'disk'.

 .P
 .P

-If no matching configuration is found, the default kernel device name is used.
-.SH "EXAMPLE"
+.RI "A sample " udev.rules " might look like this:"
+.sp

 .nf
 .nf

+# if /sbin/scsi_id returns "OEM 0815" device will be called disk1
+CALLOUT, BUS="scsi", PROGRAM="/sbin/scsi_id", ID="OEM 0815", NAME="disk1"
+

 # USB printer to be called lp_color
 LABEL, BUS="usb", serial="W09090207101241330", NAME="lp_color"
 
 # sound card with PCI bus id 00:0b.0 to be called dsp
 # USB printer to be called lp_color
 LABEL, BUS="usb", serial="W09090207101241330", NAME="lp_color"
 
 # sound card with PCI bus id 00:0b.0 to be called dsp

-NUMBER, BUS="pci", id="00:0b.0", NAME="dsp"
+NUMBER, BUS="pci", ID="00:0b.0", NAME="dsp"

 
 # USB mouse at third port of the second hub to be called mouse1
 
 # USB mouse at third port of the second hub to be called mouse1

-TOPOLOGY, BUS="usb", place="2.3", NAME="mouse1"
+TOPOLOGY, BUS="usb", PLACE="2.3", NAME="mouse1"

 
 # ttyUSB1 should always be called pda
 REPLACE, KERNEL="ttyUSB1", NAME="pda"
 
 # ttyUSB1 should always be called pda
 REPLACE, KERNEL="ttyUSB1", NAME="pda"

+
+# USB webcams with symlinks to be called webcam0, webcam1, ...
+LABEL, BUS="usb", model="WebCam Version 3", NAME="video%n", SYMLINK="webcam%n"

 .fi
 .fi

+.P
+Permissions and ownership for the created device files may specified at
+.I /etc/udev/udev.permissions
+or specified by the
+.I udev_permission
+value in the
+.I /etc/udev/udev.conf
+file.
+.br
+Every line lists a device name followed by owner, group and permission
+mode. All values are separated by colons. The name field may contain a
+pattern to apply the values to a whole class of devices.
+.br
+If
+.B udev
+was built using klibc or is used before the user database is accessible (e.g.
+.BR initrd "(4)), only numeric owner and group values may be used."
+.sp
+.RI "A sample " udev.permissions " might look like this:"
+.sp
+.nf
+#name:user:group:mode
+input/*:root:root:644
+ttyUSB1:0:8:0660
+video*:root:video:0660
+dsp1:::0666
+.fi
+.P
+A number of different fields in the above configuration files support a simple
+form of shell style pattern matching. It supports the following pattern characters:
+.TP
+.B *
+Matches zero, one, or more characters.
+.TP
+.B ?
+Matches any single character, but does not match zero characters.
+.TP
+.B [ ]
+Matches any single character specified within the brackets. For example, the
+pattern string "tty[SR]" would match either "ttyS" or "ttyR".  Ranges are also
+supported within this match with the '-' character.  For example, to match on
+the range of all digits, the pattern [0-9] would be used. If the first character
+following the '[' is a '!' then any character not enclosed is matched.

 .SH "FILES"
 .nf
 .SH "FILES"
 .nf

-.ft B
-.ft

 /sbin/udev                           udev program
 /sbin/udev                           udev program

-/etc/udev/*                          udev config and database files
+/etc/udev/*                          udev config files

 /etc/hotplug.d/default/udev.hotplug  hotplug symlink to udev program
 .fi
 .LP
 .SH "SEE ALSO"
 /etc/hotplug.d/default/udev.hotplug  hotplug symlink to udev program
 .fi
 .LP
 .SH "SEE ALSO"

-.B hotplug (8)
+.BR hotplug (8)

 .PP
 The
 .I http://linux-hotplug.sourceforge.net/
 web site.
 .SH AUTHORS
 .PP
 The
 .I http://linux-hotplug.sourceforge.net/
 web site.
 .SH AUTHORS

-udev was developed by Greg Kroah-Hartman <greg@kroah.com> with much help from
-Dan Stekloff <dsteklof@us.ibm.com> and many others.
+.B udev
+was developed by Greg Kroah-Hartman <greg@kroah.com> with much help from
+Dan Stekloff <dsteklof@us.ibm.com>, Kay Sievers <kay.sievers@vrfy.org>, and
+many others.