NAME
xmodmap - utility for modifying keymaps in X

SYNOPSIS
xmodmap [-options ...] [filename]

DESCRIPTION
The xmodmap program is used to edit and display the keyboard
modifier map and keymap table that are used by client appli-
cations to convert event keycodes into keysyms. It is usu-
ally run from the user’s session startup script to configure
the keyboard according to personal tastes.

OPTIONS
The following options may be used with xmodmap:

-display display
This option specifies the host and display to use.

-help This option indicates that a brief description of
the command line arguments should be printed on the
standard error channel. This will be done whenever
an unhandled argument is given to xmodmap.

-grammar
This option indicates that a help message describing
the expression grammar used in files and with -e
expressions should be printed on the standard error.

-verbose
This option indicates that xmodmap should print log-
ging information as it parses its input.

-quiet This option turns off the verbose logging. This is
the default.

-n This option indicates that xmodmap should not change
the mappings, but should display what it would do,
like make(1) does when given this option.

-e expression
This option specifies an expression to be executed.
Any number of expressions may be specified from the
command line.

-pm This option indicates that the current modifier map
should be printed on the standard output.

-pk This option indicates that the current keymap table
should be printed on the standard output.

-pke This option indicates that the current keymap table
should be printed on the standard output in the form
of expressions that can be fed back to xmodmap.

-pp This option indicates that the current pointer map
should be printed on the standard output.

- A lone dash means that the standard input should be
used as the input file.

The filename specifies a file containing xmodmap expressions
to be executed. This file is usually kept in the user’s
home directory with a name like .xmodmaprc.

EXPRESSION GRAMMAR
The xmodmap program reads a list of expressions and parses
them all before attempting to execute any of them. This
makes it possible to refer to keysyms that are being rede-
fined in a natural way without having to worry as much about
name conflicts.

keycode NUMBER = KEYSYMNAME ...
The list of keysyms is assigned to the indicated
keycode (which may be specified in decimal, hex or
octal and can be determined by running the xev pro-
gram.

keycode any = KEYSYMNAME ...
If no existing key has the specified list of keysyms
assigned to it, a spare key on the keyboard is
selected and the keysyms are assigned to it. The
list of keysyms may be specified in decimal, hex or
octal.

keysym KEYSYMNAME = KEYSYMNAME ...
The KEYSYMNAME on the left hand side is translated
into matching keycodes used to perform the
corresponding set of keycode expressions. The list
of keysym names may be found in the header file
<X11/keysymdef.h> (without the XK_ prefix) or the
keysym database <XRoot>/lib/X11/XKeysymDB, where
<XRoot> refers to the root of the X11 install tree.
Note that if the same keysym is bound to multiple
keys, the expression is executed for each matching
keycode.

clear MODIFIERNAME
This removes all entries in the modifier map for the
given modifier, where valid name are: Shift, Lock,
Control, Mod1, Mod2, Mod3, Mod4, and Mod5 (case does
not matter in modifier names, although it does
matter for all other names). For example, "clear
Lock" will remove all any keys that were bound to
the shift lock modifier.

add MODIFIERNAME = KEYSYMNAME ...
This adds all keys containing the given keysyms to
the indicated modifier map. The keysym names are
evaluated after all input expressions are read to
make it easy to write expressions to swap keys (see
the EXAMPLES section).

remove MODIFIERNAME = KEYSYMNAME ...
This removes all keys containing the given keysyms
from the indicated modifier map. Unlike add, the
keysym names are evaluated as the line is read in.
This allows you to remove keys from a modifier
without having to worry about whether or not they
have been reassigned.

pointer = default
This sets the pointer map back to its default set-
tings (button 1 generates a code of 1, button 2 gen-
erates a 2, etc.).

pointer = NUMBER ...
This sets to pointer map to contain the indicated
button codes. The list always starts with the first
physical button.

Lines that begin with an exclamation point (!) are taken as
comments.

If you want to change the binding of a modifier key, you
must also remove it from the appropriate modifier map.

EXAMPLES
Many pointers are designed such that the first button is
pressed using the index finger of the right hand. People
who are left-handed frequently find that it is more comfort-
able to reverse the button codes that get generated so that
the primary button is pressed using the index finger of the
left hand. This could be done on a 3 button pointer as fol-
lows:

% xmodmap -e "pointer = 3 2 1"

Many applications support the notion of Meta keys (similar
to Control keys except that Meta is held down instead of
Control). However, some servers do not have a Meta keysym
in the default keymap table, so one needs to be added by
hand. The following command will attach Meta to the Multi-
language key (sometimes labeled Compose Character). It also
takes advantage of the fact that applications that need a
Meta key simply need to get the keycode and don’t require
the keysym to be in the first column of the keymap table.
This means that applications that are looking for a
Multi_key (including the default modifier map) won’t notice
any change.

% xmodmap -e "keysym Multi_key = Multi_key Meta_L"

Similarly, some keyboards have an Alt key but no Meta key.
In that case the following may be useful:

% xmodmap -e "keysym Alt_L = Meta_L Alt_L"

One of the more simple, yet convenient, uses of xmodmap is
to set the keyboard’s "rubout" key to generate an alternate
keysym. This frequently involves exchanging Backspace with
Delete to be more comfortable to the user. If the ttyModes
resource in xterm is set as well, all terminal emulator win-
dows will use the same key for erasing characters:

% xmodmap -e "keysym BackSpace = Delete"
% echo "XTerm*ttyModes: erase ^?" | xrdb -merge

Some keyboards do not automatically generate less than and
greater than characters when the comma and period keys are
shifted. This can be remedied with xmodmap by resetting the
bindings for the comma and period with the following
scripts:

!
! make shift-, be < and shift-. be >
!
keysym comma = comma less
keysym period = period greater

One of the more irritating differences between keyboards is
the location of the Control and Shift Lock keys. A common
use of xmodmap is to swap these two keys as follows:

!
! Swap Caps_Lock and Control_L
!
remove Lock = Caps_Lock
remove Control = Control_L
keysym Control_L = Caps_Lock
keysym Caps_Lock = Control_L
add Lock = Caps_Lock
add Control = Control_L

The keycode command is useful for assigning the same keysym
to multiple keycodes. Although unportable, it also makes it
possible to write scripts that can reset the keyboard to a
known state. The following script sets the backspace key to
generate Delete (as shown above), flushes all existing caps
lock bindings, makes the CapsLock key be a control key, make
F5 generate Escape, and makes Break/Reset be a shift lock.

!
! On the HP, the following keycodes have key caps as listed:
!
! 101 Backspace
! 55 Caps
! 14 Ctrl
! 15 Break/Reset
! 86 Stop
! 89 F5
!
keycode 101 = Delete
keycode 55 = Control_R
clear Lock
add Control = Control_R
keycode 89 = Escape
keycode 15 = Caps_Lock
add Lock = Caps_Lock

ENVIRONMENT
DISPLAY to get default host and display number.

SEE ALSO
X(1), xev(1), Xlib documentation on key and pointer events

BUGS
Every time a keycode expression is evaluated, the server
generates a MappingNotify event on every client. This can
cause some thrashing. All of the changes should be batched
together and done at once. Clients that receive keyboard
input and ignore MappingNotify events will not notice any
changes made to keyboard mappings.

Xmodmap should generate "add" and "remove" expressions
automatically whenever a keycode that is already bound to a
modifier is changed.

There should be a way to have the remove expression accept
keycodes as well as keysyms for those times when you really
mess up your mappings.

AUTHOR
Jim Fulton, MIT X Consortium, rewritten from an earlier ver-
sion by David Rosenthal of Sun Microsystems.