[PATCH] Added line to udev.permissions.redhat

[elogind.git] / udev.8

diff --git a/udev.8 b/udev.8
index d7999aadfd182a686e3c17a063c52530e1bdc8e6..8ebcf7bd997e4c66bda8ea4fb3d524dec41246a0 100644 (file)
--- a/udev.8
+++ b/udev.8
@@ -3,11 +3,34 @@
 udev \- Linux configurable dynamic device naming support
 .SH SYNOPSIS
 .BI udev " hotplug-subsystem"
 udev \- Linux configurable dynamic device naming support
 .SH SYNOPSIS
 .BI udev " hotplug-subsystem"

+.P
+The environment must provide the following variables:
+.TP
+.B ACTION
+.IR add " or " remove
+signifies the connection or disconnection of a device.
+.TP
+.B DEVPATH
+The sysfs devpath of the device without the mountpoint but a leading slash.
+.P
+Additional optional environment variables:
+.TP
+.B UDEV_CONFIG_FILE
+Overrides the default location of the
+.B udev
+config file.
+.TP
+.B UDEV_NO_SLEEP
+The default behavior of
+.B udev
+is to wait until all the sysfs files of the device chain are populated. If set
+.B udev
+will continue, regardless of the state of the device representation.

 .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.
+It provides a dynamic device directory contaning only the files for
+actually present devices.

 .P
 As part of the
 .B hotplug
 .P
 As part of the
 .B hotplug


@@ -18,7 +41,7 @@ On device creation,
 .B udev
 reads the sysfs directory of the given device to collect device attributes
 like label, serial number or bus device number.
 .B udev
 reads the sysfs directory of the given device to collect device attributes
 like label, serial number or bus device number.

-These attributes may used as keys to determine a
+These attributes may be used as keys to determine a

 unique name for device file creation.
 .B udev
 maintains a database for devices present on the system.
 unique name for device file creation.
 .B udev
 maintains a database for devices present on the system.


@@ -30,27 +53,27 @@ queries its database for the name of the device file to be deleted.
 All
 .B udev
 configuration files consist of a set of lines of text.  All empty
 All
 .B udev
 configuration files consist of a set of lines of text.  All empty

-lines, and lines beginning with a '#' will be ignored.
+lines and lines beginning with a '#' will be ignored.

 .P
 
 .B udev
 expects its main configuration file at
 .IR /etc/udev/udev.conf .
 .P
 
 .B udev
 expects its main configuration file at
 .IR /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:
+The file consists of a set of variables and values allowing the user to
+override default udev values. The following variables can be overridden
+in this file:

 .TP
 .B udev_root
 .TP
 .B udev_root

-This is the where in the filesystem to place the device nodes.  The default
-value for this is
+Indicates where to place the device nodes in the filesystem. The default
+value is

 .IR /udev/ .
 .TP
 .B udev_db
 .IR /udev/ .
 .TP
 .B udev_db

-The name and location of the udev database.  The default value for this is
+The name and location of the udev database. The default value is

 .IR /udev/.udev.tdb .
 .TP
 .B udev_rules
 .IR /udev/.udev.tdb .
 .TP
 .B udev_rules

-This is the location of the udev rules file.  The default value for this is
+This is the location of the udev rules file. The default value for this is

 .IR /etc/udev/udev.rules .
 If a directory is specified, the whole directory is
 scanned for files ending with
 .IR /etc/udev/udev.rules .
 If a directory is specified, the whole directory is
 scanned for files ending with


@@ -66,32 +89,32 @@ and all permission files are read in lexical order.
 .TP
 .B udev_log
 If you want udev to log some information to the syslog for every node created or
 .TP
 .B udev_log
 If you want udev to log some information to the syslog for every node created or

-removed. The default value for this is
+removed. The default value is

 .IR yes .
 .TP
 .B default_mode
 .IR yes .
 .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
+This is the default mode for all nodes not explicitely matching in the
+permissions file. The default value is

 .IR 0666 .
 .TP
 .B default_owner
 .IR 0666 .
 .TP
 .B default_owner

-This is the default owner for all nodes that have no explicit match in the
-permissions file.  The default value for this is
+This is the default owner for all nodes not explicitely matching in the
+permissions file. The default value is

 .IR root .
 .TP
 .B default_group
 .IR root .
 .TP
 .B default_group

-This is the default group for all nodes that have no explicit match in the
-permissions file.  The default value for this is
+This is the default group for all nodes not explicitely matching in the
+permissions file. The default value is

 .IR root .
 .br
 .P
 .RI "A sample " udev.conf " might look like this:
 .sp
 .nf
 .IR root .
 .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 - where to place the device nodes in the filesystem

 udev_root="/udev/"
 
 udev_root="/udev/"
 

-# udev_db - The name and location of the udev database.
+# udev_db - The name and location of the udev database

 udev_db="/udev/.udev.tdb"
 
 # udev_rules - The location of the directory where to look for files
 udev_db="/udev/.udev.tdb"
 
 # udev_rules - The location of the directory where to look for files


@@ -104,22 +127,22 @@ udev_permissions="/etc/udev/udev.permissions"
 # udev_log - set to "yes" if you want logging, else "no"
 udev_log="yes"
 
 # udev_log - set to "yes" if you want logging, else "no"
 udev_log="yes"
 

-# default_mode - set the default mode for all nodes that have no
-#                explicit match in the permissions file
+# default_mode - set the default mode for all nodes not
+#                explicitely matching in the permissions file

 default_mode="0666"
 
 default_mode="0666"
 

-# default_owner - set the default owner for all nodes that have no
-#                 explicit match in the permissions file
+# default_owner - set the default owner for all nodes not
+#                 explicitely matching in the permissions file

 default_owner="root"
 
 default_owner="root"
 

-# default_group - set the default group for all nodes that have no
-#                 explicit match in the permissions file
+# default_group - set the default group for all nodes not
+#                 explicitely matching in the permissions file

 default_group="root"
 .fi
 .P
 default_group="root"
 .fi
 .P

-The rules for udev to use when naming devices may specified at
+The rules for udev to use when naming devices may specified in

 .I /etc/udev/udev.rules
 .I /etc/udev/udev.rules

-or specified by the
+or by the

 .I udev_rules
 value in the
 .I /etc/udev/udev.conf
 .I udev_rules
 value in the
 .I /etc/udev/udev.conf


@@ -128,16 +151,15 @@ file.
 Every line in the rules file defines the mapping between device attributes
 and the device file name. One ore more keys are specified to match a rule
 with the current device. If all keys are matching, the rule will be applied
 Every line in the rules file defines the mapping between device attributes
 and the device file name. One ore more keys are specified to match a rule
 with the current device. If all keys are matching, the rule will be applied

-and the name is used for the device node. One or more optional symlinks
-targeting the node may be specified.
+and the name is used for the device node.

 .br
 If no matching rule is found, the default kernel device name is used.
 .P
 .br
 If no matching rule is found, the default kernel device name is used.
 .P

-The line format is:
+Every rule consists of a list a comma separated fields:

 .sp
 .sp

-.I key,[key,...] name [, symlink]
+.IR "key " ,[ "key " ,...] " name " [, " symlink" ]

 .sp
 .sp

-where keys are:
+where fields are:

 .TP
 .B BUS
 Match the bus type of the device.
 .TP
 .B BUS
 Match the bus type of the device.


@@ -155,34 +177,56 @@ Match the topological position on bus, like physical port of USB device
 .BI SYSFS{ filename }
 Match sysfs device attribute like label, vendor, USB serial number, SCSI UUID
 or file system label.  Up to 5 different sysfs files can be checked, with
 .BI SYSFS{ filename }
 Match sysfs device attribute like label, vendor, USB serial number, SCSI UUID
 or file system label.  Up to 5 different sysfs files can be checked, with

-all of the values being required in order to match the rule.
+all of the values being required to match the rule.
+.br
+Trailing whitespace characters in the sysfs attribute value are ignored, if
+the key doesn't have any trailing whitespace characters by itself.

 .TP
 .B PROGRAM
 Call external program. This key is valid if the program returns successful.
 .TP
 .B PROGRAM
 Call external program. This key is valid if the program returns successful.

-The string returned by the program may additionally matched with the
+The environment variables of
+.B udev
+are also available for the program.
+.br
+The string returned by the program may be additionally matched with the

 .B RESULT
 key.
 .TP
 .B RESULT
 Match the returned string of the last
 .B PROGRAM
 .B RESULT
 key.
 .TP
 .B RESULT
 Match the returned string of the last
 .B PROGRAM

-call. This key may used in any following rule after a
+call. This key may be used in any following rule after a

 .B PROGRAM
 call.
 .B PROGRAM
 call.

-.P
-The
+.TP

 .B NAME
 .B NAME

-field given with the attribute
+The name of the node to be created.
+.br
+If given with the attribute

 .BR NAME{ all_partitions }
 .BR NAME{ all_partitions }

-will  create all 15 partitions of a blockdevice.
+it will  create all 15 partitions of a blockdevice.

 This may be useful for removable media devices.
 This may be useful for removable media devices.

+.TP
+.B SYMLINK
+The name of a symlink targeting the node. Multiple symlinks may be
+specified by separating the names by the space character.
+.br
+If both the name and the symlink fields are omitted or its
+values empty, the device will be ignored and no node will be created.
+.br
+If only the symlink field is given and the name field is omitted,
+the rule will not be applied immediatly, but the symlink field is added
+to the symlink list of the rule which will create the node.
+This makes it possible to specify additional symlinks in a possibly
+separate rules file, while the device nodes are maintained by the
+distribution provided rules file.

 .P
 .RB "The " NAME " ," SYMLINK " and " PROGRAM
 fields support simple printf-like string substitution:
 .TP
 .B %n
 The "kernel number" of the device.
 .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'
+For example, 'sda3' has a "kernel number" of '3'.

 .TP
 .B %k
 The "kernel name" for the device.
 .TP
 .B %k
 The "kernel name" for the device.


@@ -197,22 +241,25 @@ The kernel minor number for the device.
 The bus id for the device.
 .TP
 .B %c
 The bus id for the device.
 .TP
 .B %c

-The
+The string returned from the execution of

 .B PROGRAM
 .B PROGRAM

-returned string.

 (This does not work within the
 .B PROGRAM
 field for the obvious reason.)
 .br
 (This does not work within the
 .B PROGRAM
 field for the obvious reason.)
 .br

-A single part of the string, separated by the space character
-my be selected by specifying the part number as a attribute:
+A single part of the string, separated by a space character
+may be selected by specifying the part number as a attribute:

 .BI %c{ part }
 .TP
 .BI %s{ filename }
 The content of a sysfs attribute.
 .TP
 .B %%
 .BI %c{ part }
 .TP
 .BI %s{ filename }
 The content of a sysfs attribute.
 .TP
 .B %%

-The '%' char itself.
+The '%' character itself.
+.P
+The count of charcters to insert may be limited by specifying
+the format length value. For example, '%3s{file}' will only insert
+the first three characters of the sysfs attribute.

 .P
 .RI "A sample " udev.rules " might look like this:"
 .sp
 .P
 .RI "A sample " udev.rules " might look like this:"
 .sp


@@ -223,7 +270,7 @@ BUS="scsi", PROGRAM="/sbin/scsi_id", RESULT="OEM 0815", NAME="disk1"
 # USB printer to be called lp_color
 BUS="usb", SYSFS{serial}="W09090207101241330", NAME="lp_color"
 
 # USB printer to be called lp_color
 BUS="usb", SYSFS{serial}="W09090207101241330", NAME="lp_color"
 

-# SCSI disk with a specific vendor and model number is to be called boot
+# SCSI disk with a specific vendor and model number will be called boot

 BUS="scsi", SYSFS{vendor}="IBM", SYSFS{model}="ST336", NAME="boot%n"
 
 # sound card with PCI bus id 00:0b.0 to be called dsp
 BUS="scsi", SYSFS{vendor}="IBM", SYSFS{model}="ST336", NAME="boot%n"
 
 # sound card with PCI bus id 00:0b.0 to be called dsp


@@ -239,9 +286,9 @@ KERNEL="ttyUSB1", NAME="pda", SYMLINK="palmtop handheld"
 BUS="usb", SYSFS{model}="XV3", NAME="video%n", SYMLINK="webcam%n"
 .fi
 .P
 BUS="usb", SYSFS{model}="XV3", NAME="video%n", SYMLINK="webcam%n"
 .fi
 .P

-Permissions and ownership for the created device files may specified at
+Permissions and ownership for the created device files may specified in

 .I /etc/udev/udev.permissions
 .I /etc/udev/udev.permissions

-or specified by the
+or by the

 .I udev_permission
 value in the
 .I /etc/udev/udev.conf
 .I udev_permission
 value in the
 .I /etc/udev/udev.conf


@@ -261,6 +308,17 @@ video*:root:video:0660
 dsp1:::0666
 .fi
 .P
 dsp1:::0666
 .fi
 .P

+The value
+.I $local
+can be used instead of a specific username.  In that case, udev will determine
+the current local user at the time of device node creation and substitute
+that username as the owner of the new device node.  This is useful, for
+example, to let hot-plugged devices, such as cameras, be owned by the user at
+the current console.  Note that if no user is currently logged in, or if udev
+otherwise fails to determine a current user, the
+.I default_owner
+value is used in lieu.
+.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
 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


@@ -273,9 +331,9 @@ Matches any single character, but does not match zero characters.
 .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
 .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.
+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 '!', any character not enclosed is matched.

 .SH "FILES"
 .nf
 /sbin/udev                           udev program
 .SH "FILES"
 .nf
 /sbin/udev                           udev program


@@ -285,10 +343,11 @@ following the '[' is a '!' then any character not enclosed is matched.
 .LP
 .SH "SEE ALSO"
 .BR udevinfo (8),
 .LP
 .SH "SEE ALSO"
 .BR udevinfo (8),

+.BR udevd (8),

 .BR hotplug (8)
 .PP
 The
 .BR hotplug (8)
 .PP
 The

-.I http://linux-hotplug.sourceforge.net/
+.I http://linux\-hotplug.sourceforge.net/

 web site.
 .SH AUTHORS
 .B udev
 web site.
 .SH AUTHORS
 .B udev