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KEYMAPS(5)									       KEYMAPS(5)

NAME
       keymaps - keyboard table descriptions for loadkeys and dumpkeys

DESCRIPTION
       These  files  are  used by loadkeys(1) to modify the translation tables used by the kernel
       keyboard driver and generated by dumpkeys(1) from those translation tables.

       The format of these files is vaguely similar to the one accepted by xmodmap(1).	The  file
       consists of charset or key or string definition lines interspersed with comments.

       Comments  are introduced with !	or # characters and continue to the end of the line. Any-
       thing following one of these characters on that line is ignored. Note that  comments  need
       not begin from column one as with xmodmap(1).

       The  syntax  of	keymap files is line oriented; a complete definition must fit on a single
       logical line. Logical lines can, however, be split into multiple physical lines by  ending
       each subline with the backslash character (\).

INCLUDE FILES
       A keymap can include other keymaps using the syntax

	      include "pathname"

CHARSET DEFINITIONS
       A character set definition line is of the form:

	      charset "iso-8859-x"

       It  defines  how  following keysyms are to be interpreted.  For example, in iso-8859-1 the
       symbol mu (or micro) has code 0265, while in iso-8859-7 the letter mu has code 0354.

COMPLETE KEYCODE DEFINITIONS
       Each complete key definition line is of the form:

	      keycode keynumber = keysym keysym keysym...

       keynumber is the internal identification number of the key, roughly equivalent to the scan
       code  of  it.  keynumber can be given in decimal, octal or hexadecimal notation.  Octal is
       denoted by a leading zero and hexadecimal by the prefix 0x.

       Each of the keysyms represent keyboard actions, of which up to 256 can be bound to a  sin-
       gle  key. The actions available include outputting character codes or character sequences,
       switching consoles or keymaps, booting the machine etc. (The complete list can be obtained
       from dumpkeys(1) by saying  dumpkeys -l .)

       Each keysym may be prefixed by a '+' (plus sign), in wich case this keysym is treated as a
       "letter" and therefore affected by the "CapsLock" the same way as by "Shift" (to  be  cor-
       rect,  the CapsLock inverts the Shift state).  The ASCII letters ('a'-'z' and 'A'-'Z') are
       made CapsLock'able by default.  If Shift+CapsLock should not produce a lower case  symbol,
       put lines like

	      keycode 30 = +a  A

       in the map file.

       Which of the actions bound to a given key is taken when it is pressed depends on what mod-
       ifiers are in effect at that moment.  The keyboard driver supports 9 modifiers. These mod-
       ifiers  are  labeled  (completely arbitrarily) Shift, AltGr, Control, Alt, ShiftL, ShiftR,
       CtrlL, CtrlR and CapsShift.  Each of these modifiers has an associated weight of power  of
       two according to the following table:

	      modifier		      weight

	      Shift
					1
	      AltGr
					2
	      Control
					4
	      Alt
					8
	      ShiftL
				       16
	      ShiftR
				       32
	      CtrlL
				       64
	      CtrlR		      128
	      CapsShift 	      256

       The  effective  action of a key is found out by adding up the weights of all the modifiers
       in effect. By default, no modifiers are in effect, so action number zero, i.e. the one  in
       the  first  column in a key definition line, is taken when the key is pressed or released.
       When e.g. Shift and Alt modifiers are in effect, action number nine (from the 10th column)
       is the effective one.

       Changing  the state of what modifiers are in effect can be achieved by binding appropriate
       key actions to desired keys. For example, binding the symbol Shift to a key sets the Shift
       modifier  in  effect when that key is pressed and cancels the effect of that modifier when
       the key is released. Binding AltGr_Lock to a key sets AltGr in  effect  when  the  key  is
       pressed	and  cancels the effect when the key is pressed again.	(By default Shift, AltGr,
       Control and Alt are bound to the keys that bear a similar  label;  AltGr  may  denote  the
       right Alt key.)

       Note that you should be very careful when binding the modifier keys, otherwise you can end
       up with an unusable keyboard mapping. If you for example define a key to have  Control  in
       its  first  column and leave the rest of the columns to be VoidSymbols, you're in trouble.
       This is because pressing the key puts Control modifier in effect and the following actions
       are  looked  up from the fifth column (see the table above). So, when you release the key,
       the action from the fifth column is taken. It has VoidSymbol in it,  so	nothing  happens.
       This  means  that  the Control modifier is still in effect, although you have released the
       key.  Re-pressing and releasing the key has no effect. To avoid this,  you  should  always
       define all the columns to have the same modifier symbol. There is a handy short-hand nota-
       tion for this, see below.

       keysyms can be given in decimal, octal, hexadecimal, unicode or	symbolic  notation.   The
       numeric	notations  use	the same format as with keynumber.  Unicode notation is "U+" fol-
       lowed  by  four	hexadecimal  digits.   The  symbolic  notation	resembles  that  used  by
       xmodmap(1).  Notable differences are the number symbols. The numeric symbols '0', ..., '9'
       of xmodmap(1) are replaced with the corresponding words 'zero', 'one', ... 'nine' to avoid
       confusion with the numeric notation.

       It should be noted that using numeric notation for the keysyms is highly unportable as the
       key action numbers may vary from one kernel version to another  and  the  use  of  numeric
       notations  is  thus  strongly discouraged. They are intended to be used only when you know
       there is a supported keyboard action in your kernel for	which  your  current  version  of
       loadkeys(1) has no symbolic name.

       There  is  a  number of short-hand notations to add readability and reduce typing work and
       the probability of typing-errors.

       First of all, you can give a map specification line, of the form

	      keymaps 0-2,4-5,8,12

       to indicate that the lines of the keymap will not specify all 256 columns,  but	only  the
       indicated ones. (In the example: only the plain, Shift, AltGr, Control, Control+Shift, Alt
       and Control+Alt maps, that is, 7 columns instead of 256.)  When no such line is given, the
       keymaps 0-M will be defined, where M+1 is the maximum number of entries found in any defi-
       nition line.

       Next, you can leave off any trailing  VoidSymbol  entries  from	a  key	definition  line.
       VoidSymbol  denotes  a  keyboard  action which produces no output and has no other effects
       either. For example, to define key number 30 to output 'a'  unshifted,  'A'  when  pressed
       with Shift and do nothing when pressed with AltGr or other modifiers, you can write

	      keycode  30 = a	  A

       instead of the more verbose

	      keycode  30 = a	  A    VoidSymbol     VoidSymbol \
			VoidSymbol VoidSymbol VoidSymbol ...

       For  added  convenience, you can usually get off with still more terse definitions. If you
       enter a key definition line with only and exactly one action code after the  equals  sign,
       it  has	a  special  meaning. If the code (numeric or symbolic) is not an ASCII letter, it
       means the code is implicitly replicated through all columns being  defined.   If,  on  the
       other  hand, the action code is an ASCII character in the range 'a', ..., 'z' or 'A', ...,
       'Z' in the ASCII collating sequence, the following definitions are made for the	different
       modifier  combinations,	provided  these are actually being defined.  (The table lists the
       two possible cases: either the single action code is a lower case letter, denoted  by  'x'
       or an upper case letter, denoted by 'Y'.)

	   modifier		   symbol

	   none 		   x		  Y
	   Shift		   X		  y
	   AltGr		   x		  Y
	   Shift+AltGr		   X		  y
	   Control		   Control_x	  Control_y
	   Shift+Control	   Control_x	  Control_y
	   AltGr+Control	   Control_x	  Control_y
	   Shift+AltGr+Control	   Control_x	  Control_y
	   Alt			   Meta_x	  Meta_Y
	   Shift+Alt		   Meta_X	  Meta_y
	   AltGr+Alt		   Meta_x	  Meta_Y
	   Shift+AltGr+Alt	   Meta_X	  Meta_y
	   Control+Alt		   Meta_Control_x Meta_Control_y
	   Shift+Control+Alt	   Meta_Control_x Meta_Control_y
	   AltGr+Control+Alt	   Meta_Control_x Meta_Control_y
	   Shift+AltGr+Control+Alt Meta_Control_x Meta_Control_y

SINGLE MODIFIER DEFINITIONS
       All the previous forms of key definition lines always define all the M+1 possible modifier
       combinations being defined, whether the line actually contains that many action	codes  or
       not.   There  is,  however,  a variation of the definition syntax for defining only single
       actions to a particular modifier combination of a key. This is especially useful,  if  you
       load  a	keymap	which  doesn't	match your needs in only some modifier combinations, like
       AltGr+function keys. You can then make a small local file redefining only  those  modifier
       combinations and loading it after the main file.  The syntax of this form is:

       { plain | <modifier sequence> } keycode keynumber = keysym

       , e.g.,
	      plain keycode 14 = BackSpace
	      control alt keycode 83 = Boot
	      alt keycode 105 = Decr_Console
	      alt keycode 106 = Incr_Console
       Using  "plain" will define only the base entry of a key (i.e. the one with no modifiers in
       effect) without affecting the bindings of other modifier combinations of that key.

STRING DEFINITIONS
       In addition to comments and key definition lines, a keymap can contain string definitions.
       These  are  used  to define what each function key action code sends. The syntax of string
       definitions is:

	      string keysym = "text"

       text can contain literal characters, octal character codes in the format of backslash fol-
       lowed by up to three octal digits, and the three escape sequences \n, \\, and \", for new-
       line, backslash and quote, respectively.

COMPOSE DEFINITIONS
       Then there may also be compose definitions. They have syntax

	      compose 'char' 'char' to 'char'
       and describe how two bytes are combined to form a third one (when a dead accent or compose
       key is used).  This is used to get accented letters and the like on a standard keyboard.

ABBREVIATIONS
       Various abbreviations can be used with kbd-0.96 and later.

       strings as usual
	      Defines the usual values of the strings (but not the keys they are bound to).

       compose as usual for "iso-8859-1"
	      Defines the usual compose combinations.

       To find out what keysyms there are available for use in keymaps, use the command

	      dumpkeys --long-info

       Unfortunately,  there  is  currently no description of what each symbol does. It has to be
       guessed from the name or figured out from the kernel sources.

EXAMPLES
       (Be careful to use a keymaps line, like the first line of `dumpkeys`, or "keymaps 0-15" or
       so.)

       The following entry exchanges the left Control key and the Caps Lock key on the keyboard:

	      keycode  58 = Control
	      keycode  29 = Caps_Lock

       Key  number  58	is  normally the Caps Lock key, and key number 29 is normally the Control
       key.

       The following entry sets the Shift and Caps Lock keys to behave more nicely, like in older
       typewriters.  That  is,	pressing Caps Lock key once or more sets the keyboard in CapsLock
       state and pressing either of the Shift keys releases it.

	      keycode  42 = Uncaps_Shift
	      keycode  54 = Uncaps_Shift
	      keycode  58 = Caps_On

       The following entry sets the layout of the edit pad in the enhanced keyboard  to  be  more
       like that in the VT200 series terminals:

	      keycode 102 = Insert
	      keycode 104 = Remove
	      keycode 107 = Prior
	      shift keycode 107 = Scroll_Backward
	      keycode 110 = Find
	      keycode 111 = Select
	      control alt   keycode 111 = Boot
	      control altgr keycode 111 = Boot

       Here's  an  example  to	bind the string "du\ndf\n" to the key AltGr-D. We use the "spare"
       action code F100 not normally bound to any key.

	      altgr keycode 32 = F100
	      string F100 = "du\ndf\n"

SEE ALSO
       loadkeys(1), dumpkeys(1), showkey(1), xmodmap(1)

					  24 April 1998 			       KEYMAPS(5)
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