XMODMAP(1) MachTen Programmer’s Manual XMODMAP(1)

xmodmap - utility for modifying keymaps in X

xmodmap [-options ...] [filename]

The xmodmap program is used to edit and display the key-
board modifier map and keymap table that are used by
client applications to convert event keycodes into
keysyms. It is usually run from the user’s session
startup script to configure the keyboard according to per-
sonal tastes.

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

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

This option indicates that xmodmap should print
logging 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

-e expression
This option specifies an expression to be exe-
cuted. 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

-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 expres-
sions to be executed. This file is usually kept in the
user’s home directory with a name like .xmodmaprc.

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.

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

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

The KEYSYMNAME on the left hand side is translated
into matching keycodes used to perform the corre-
sponding 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.

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.

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).

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
generates 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.

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 com-
fortable 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 follows:

% 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 alter-
nate 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 ter-
minal emulator windows will use the same key for erasing

% 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

! 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 fol-

! 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 key-
board 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

DISPLAY to get default host and display number.

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

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.

Jim Fulton, MIT X Consortium, rewritten from an earlier
version by David Rosenthal of Sun Microsystems.

X Version 11 Release 6 5