dumpkeys Man page

DUMPKEYS(1) General Commands Manual DUMPKEYS(1)


dumpkeys – dump keyboard translation tables


dumpkeys [ -hilfn -ccharset –help –short-info –long-info –numeric
–full-table –funcs-only –keys-only –compose-only –charset=charset


dumpkeys writes, to the standard output, the current contents of the
keyboard driver’s translation tables, in the format specified by

Using the various options, the format of the output can be controlled
and also other information from the kernel and the programs dumpkeys
and loadkeys can be obtained.


-h –help
Prints the program’s version number and a short usage message to
the program’s standard error output and exits.

-i –short-info
Prints some characteristics of the kernel’s keyboard driver. The
items shown are:

Keycode range supported by the kernel

This tells what values can be used after the keycode key‐
word in keytable files. See keymaps(5) for more informa‐
tion and the syntax of these files.

Number of actions bindable to a key

This tells how many different actions a single key can
output using various modifier keys. If the value is 16
for example, you can define up to 16 different actions to
a key combined with modifiers. When the value is 16, the
kernel probably knows about four modifier keys, which you
can press in different combinations with the key to
access all the bound actions.

Ranges of action codes supported by the kernel

This item contains a list of action code ranges in hexa‐
decimal notation. These are the values that can be used
in the right hand side of a key definition, ie. the vv’s
in a line

keycode xx = vv vv vv vv

(see keymaps(5) for more information about the format of
key definition lines). dumpkeys and loadkeys sup‐
port a symbolic notation, which is preferable to the
numeric one, as the action codes may vary from kernel to
kernel while the symbolic names usually remain the same.
However, the list of action code ranges can be used to
determine, if the kernel actually supports all the sym‐
bols loadkeys knows, or are there maybe some actions
supported by the kernel that have no symbolic name in
your loadkeys program. To see this, you compare the
range list with the action symbol list, see option
–long-info below.

Number of function keys supported by kernel

This tells the number of action codes that can be used to
output strings of characters. These action codes are tra‐
ditionally bound to the various function and editing keys
of the keyboard and are defined to send standard escape
sequences. However, you can redefine these to send common
command lines, email addresses or whatever you like.
Especially if the number of this item is greater than the
number of function and editing keys in your keyboard, you
may have some “spare” action codes that you can bind to
AltGr-letter combinations, for example, to send some use‐
ful strings. See loadkeys for more details.

Function strings

You can see you current function key definitions with the

dumpkeys –funcs-only

-l –long-info
This option instructs dumpkeys to print a long information list‐
ing. The output is the same as with the –short-info appended
with the list of action symbols supported by loadkeys and
dumpkeys, along with the symbols’ numeric values.

-n –numeric
This option causes dumpkeys to by-pass the conversion of action
code values to symbolic notation and to print the in hexadecimal
format instead.

-f –full-table
This makes dumpkeys skip all the short-hand heuristics (see
keymaps(5)) and output the key bindings in the canonical form.
First a keymaps line describing the currently defined modifier
combinations is printed. Then for each key a row with a column
for each modifier combination is printed. For example, if the
current keymap in use uses seven modifiers, every row will have
seven action code columns. This format can be useful for example
to programs that post-process the output of dumpkeys.

When this option is given, dumpkeys prints only the function key
string definitions. Normally dumpkeys prints both the key bind‐
ings and the string definitions.

When this option is given, dumpkeys prints only the key bind‐
ings. Normally dumpkeys prints both the key bindings and the
string definitions.

When this option is given, dumpkeys prints only the compose key
combinations. This option is available only if your kernel has
compose key support.

-ccharset –charset=charset
This instructs dumpkeys to interpret character code values
according to the specified character set. This affects only the
translation of character code values to symbolic names. Valid
values for charset currently are iso-8859-X, Where X is a digit
in 1-9. If no charset is specified, iso-8859-1 is used as a
default. This option produces an output line `charset
“iso-8859-X”‘, telling loadkeys how to interpret the keymap.
(For example, “division” is 0xf7 in iso-8859-1 but 0xba in

/usr/share/keymaps recommended directory for keytable files


loadkeys, keymaps(5)

1 Sep 1993 DUMPKEYS(1)

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