[PATCH] fix permission handling logic

[elogind.git] / udev.8

diff --git a/udev.8 b/udev.8
index 42239c824d943c126f61073aa5db9fbbb3d133b4..fd1b6dd2285e583c75ad1deb6e7fa038aeeeb01f 100644 (file)
--- a/udev.8
+++ b/udev.8
@@ -20,21 +20,80 @@ reads the sysfs directory of the given device to collect device attributes
 like label, serial number or bus device number.
 These attributes are treated as a key 
 to determine a unique name for device file creation.
 like label, serial number or bus device number.
 These attributes are treated as a key 
 to determine a unique name for device file creation.

-udev maintains a database for devices present on the system.
+.B udev
+maintains a database for devices present on the system.

 .br
 On device removal,
 .B udev
 queries the internal database for the name of the device file to be deleted.
 .SH "CONFIGURATION"
 .br
 On device removal,
 .B udev
 queries the internal database for the name of the device file to be deleted.
 .SH "CONFIGURATION"

-udev expects its configuration at
-.I /etc/udev/udev.config.
-The file consists of a set of lines. All empty lines and
-lines beginning with a '#' will be ignored.
+All 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
 .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 and the filename for the device. If no matching
-configuration is found, the default kernel device name is used.
+.P
+A sample \fIudev.conf\fP 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. If no matching configuration is found, the default kernel device name
+is used.

 .P
 The line format is:
 .RS
 .P
 The line format is:
 .RS


@@ -44,6 +103,11 @@ The line format is:
 .RE
 where valid methods with corresponding keys are:
 .TP
 .RE
 where valid methods with corresponding keys are:
 .TP

+.B CALLOUT
+calling external program, that returns a string to match
+.br
+keys: \fBBUS\fP, \fBPROGRAM\fP, \fBID\fP
+.TP

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


@@ -64,15 +128,54 @@ keys: \fBBUS\fP, \fBPLACE\fP
 string replacement of the kernel device name
 .br
 key: \fBKERNEL_NAME\fP
 string replacement of the kernel device name
 .br
 key: \fBKERNEL_NAME\fP

-.TP
+.P
+The methods are applied in the following order:

 .B CALLOUT
 .B CALLOUT

-calling external program, that returns a string to match
-.br
-keys: \fBBUS\fP, \fBPROGRAM\fP, \fBID\fP
+,
+.B LABEL
+,
+.B NUMBER
+,
+.B TOPOLOGY
+,
+.B REPLACE

 .P
 .P

-A sample \fIudev.conf\fP might look like this:
+The 
+.B NAME 
+and 
+.B PROGRAM 
+fields support simple printf-like string subtitution:
+.RS
+.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'
+.RE
+.P
+A sample \fIudev.rules\fP might look like this:

 .sp
 .nf
 .sp
 .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"
 
 # USB printer to be called lp_color
 LABEL, BUS="usb", serial="W09090207101241330", NAME="lp_color"
 


@@ -85,31 +188,45 @@ 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"
 

-# if /sbin/dev_id returns "V0815" device will be called dev0815
-CALLOUT, PROGRAM="/sbin/dev_id", BUS="pci", ID="V0815", NAME="dev0815"
+# USB webcams to be called webcam0, webcam1, ...
+LABEL, BUS="usb", model="WebCam Version 3", NAME="webcam%n"

 .fi
 .P
 Permissions and ownership for the created device files may specified at
 .fi
 .P
 Permissions and ownership for the created device files may specified at

-.I /etc/udev/udev.permissions.
+.I /etc/udev/udev.permissions
+or specified by the 
+.I udev_permission
+value in the 
+.I /etc/udev/udev.conf
+file.

 The file consists of a set of lines. All empty lines and
 lines beginning with a '#' will be ignored.
 .br
 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.
+Every line lists a device name followed by owner, group and permission
+mode. All values are separated by colons. The name field may end with a
+wildcard 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.
+.B initrd
+), only numeric owner and group values may be used.

 .sp
 A sample \fIudev.permissions\fP might look like this:
 .sp
 .nf
 #name:user:group:mode
 .sp
 A sample \fIudev.permissions\fP might look like this:
 .sp
 .nf
 #name:user:group:mode

-ttyUSB1:root:uucp:0666
+input/*:root:root:644
+ttyUSB1:0:8:0660
+video*:root:video:0660

 dsp1:::0666
 .fi
 dsp1:::0666
 .fi

-

 .SH "FILES"
 .nf
 .ft B
 .ft
 /sbin/udev                           udev program
 .SH "FILES"
 .nf
 .ft B
 .ft
 /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
 /etc/hotplug.d/default/udev.hotplug  hotplug symlink to udev program
 .fi
 .LP


@@ -120,5 +237,6 @@ The
 .I http://linux-hotplug.sourceforge.net/
 web site.
 .SH AUTHORS
 .I http://linux-hotplug.sourceforge.net/
 web site.
 .SH AUTHORS

-udev was developed by Greg Kroah-Hartman <greg@kroah.com> with much help from
+.B udev
+was developed by Greg Kroah-Hartman <greg@kroah.com> with much help from

 Dan Stekloff <dsteklof@us.ibm.com> and many others.
 Dan Stekloff <dsteklof@us.ibm.com> and many others.