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Hack 10. Redefine Keyboard Actions

This hack describes one of many ways you can customize the default
behavior of keys and key combinations for your keyboard. If you just
want to make your special function keys on your fancy Internet and
multimedia keyboard work, take a look at [Hack #28] and [Hack #29] . But if you want to fine-tune
how keystrokes affect virtual text consoles, this is the place for
you.

2.2.1. Virtual Consoles

You might recall that people used to
attach several text-based terminals to minicomputers and mainframes
so that many people could access the computer at once. Each person
could log in to the computer and work on his separate text console,
because he had his own text-based terminal connected to the main
computer.

Linux simulates that kind of behavior with a single terminal and
several virtual consoles. Even if your Linux-based computer starts up
automatically with a graphical login screen, you can get to the first
virtual text console by pressing the key combination Ctrl-Alt-F1. If
you want, you can log in and work, using text-based programs. If you
press Alt-F2 from here (or Ctrl-Alt-F2), Linux takes you to another
virtual console with another login prompt. This simulates another
separate terminal hooked up to the computer. Alt-F3 takes you to yet
another virtual console and login prompt.

You actually need to use Ctrl-Alt-Fn only when switching from an X console, such as virtual console 7. Otherwise, you can get away with just Alt-Fn.

2.2.2. Using the "Other" Alt Key

You might have noticed by now that you can switch from one text console to
another only by using the Alt key on the left side of the keyboard.
It won't work if you use the Alt key on the right
side of the keyboard with F1, F2, or any other function key. This is
not an accident. Linux is configured such that the Alt key on the
right side of the keyboard plus the F1 key will take you to virtual
console 13. The problem is that very few people use as many as 13
virtual consoles, and most Linux distributions don't
even enable more than 10 or 11 virtual consoles by default.

Because you don't need to use the Alt key on the
right side to switch to nonactive virtual consoles, you might as well
use that Alt key in the same way the left Alt key worksto take
you to virtual console 1, 2, 3, and so on. If you learn how to alter
the way the keyboard is configured so that you can use the right Alt
key to switch between virtual consoles, you will begin to understand
how to make other useful changes in how your keyboard functions.

Here's how to make the change. Dump the current
default key settings to a file with the following command (you can
log in as root, but a properly configured sudo
should give you the right to dump the file to the
/etc directory):

$ sudo dumpkeys --keys-only > 
/etc/mykeys

Now open the file (as root, preferably with
sudo) with your favorite editor and locate the
following section:

keycode  59 = F1               F13              Console_13        F25             
alt    keycode  59 = Console_1       
control    alt    keycode  59 = Console_1       
keycode  60 = F2               F14              Console_14       F26             
alt    keycode  60 = Console_2       
control    alt    keycode  60 = Console_2       
keycode  61 = F3               F15              Console_15       F27             
alt    keycode  61 = Console_3       
control    alt    keycode  61 = Console_3       
keycode  62 = F4               F16              Console_16       F28             
alt    keycode  62 = Console_4       
control    alt    keycode  62 = Console_4       
keycode  63 = F5               F17              Console_17       F29             
alt    keycode  63 = Console_5       
control    alt    keycode  63 = Console_5       
keycode  64 = F6               F18              Console_18       F30             
alt    keycode  64 = Console_6       
control    alt    keycode  64 = Console_6       
keycode  65 = F7               F19              Console_19       F31             
alt    keycode  65 = Console_7       
control    alt    keycode  65 = Console_7       
keycode  66 = F8               F20              Console_20       F32             
alt    keycode  66 = Console_8       
control    alt    keycode  66 = Console_8       
keycode  67 = F9               F21              Console_21       F33             
alt    keycode  67 = Console_9       
control    alt    keycode  67 = Console_9       
keycode  68 = F10              F22              Console_22       F34             
alt    keycode  68 = Console_10      
control    alt    keycode  68 = Console_10

The first line in the section that is relevant to the changes we want
to make starts with the keycode definition, which is keycode
59 =. A number of columns follow the equals sign, and each
column represents what is produced when you combine a modifier (such
as Shift, Ctrl, etc.) with that keycode 59. F1 appears in the first
column; so, when you press F1 alone (to produce keycode 59), you get
F1 with no modifiers (such as Shift, Ctrl, etc.). The second column
tells you what you get when you press Shift-F1, and that result is
the key F13. The third column tells you what you get when you press
Altgr (the Alt key on the right side of the keyboard)-F1, and that
takes you to Console_13.

See the sidebar How to Interpret Keycode Files for a more detailed explanation as to why the command switch --keys-only produces this particular type of abbreviated set of definitions for your keyboard configuration.

You want to change this key combination to take you to Console_1
rather than Console_13. All you have to do is change the definition
from Console_13 to Console_1.
Change Console_14 to Console_2,
and so on. Edit each starting line for every keycode definition so
that the previous section looks like the following:

keycode  59 = F1               F13              Console_1       F25             
alt    keycode  59 = Console_1       
control    alt    keycode  59 = Console_1       
keycode  60 = F2               F14              Console_2       F26             
alt    keycode  60 = Console_2       
control    alt    keycode  60 = Console_2       
keycode  61 = F3               F15              Console_3       F27             
alt    keycode  61 = Console_3       
control    alt    keycode  61 = Console_3       
keycode  62 = F4               F16              Console_4       F28             
alt    keycode  62 = Console_4       
control    alt    keycode  62 = Console_4       
keycode  63 = F5               F17              Console_5       F29             
alt    keycode  63 = Console_5       
control    alt    keycode  63 = Console_5       
keycode  64 = F6               F18              Console_6       F30             
alt    keycode  64 = Console_6       
control    alt    keycode  64 = Console_6       
keycode  65 = F7               F19              Console_7       F31             
alt    keycode  65 = Console_7       
control    alt    keycode  65 = Console_7       
keycode  66 = F8               F20              Console_8       F32             
alt    keycode  66 = Console_8       
control    alt    keycode  66 = Console_8       
keycode  67 = F9               F21              Console_9       F33             
alt    keycode  67 = Console_9       
control    alt    keycode  67 = Console_9       
keycode  68 = F10              F22              Console_10       F34             
alt    keycode  68 = Console_10      
control    alt    keycode  68 = Console_10

Save your modifications to the file /etc/mykeys.

You're not quite done. You still have to load this
new set of definitions into the system before the modifications will
work. You do that with the following command:

$ sudo loadkeys 
/etc/mykeys

Now you can use either the left or right Alt key (plus a function key
such as F1) to switch between the most frequently used virtual
consoles. The downside, if there is one, is that you can no longer
get to Console_13 or higher by pressing Altgr-F1, Altgr-F2, etc. In
most cases, however, Linux does not activate consoles above
Console_11, so you'll never miss the lost
capability.

If you want to have your computer automatically reload the new key
definitions at startup, see the sidebar Keep Your Custom Keys Intact.

2.2.3. Deep-Six the Caps Lock Key

This section describes another thing you can accomplish
by changing the keycode definitions.

I hate the Caps Lock key. I am always inadvertently hitting the key,
after which I type a full command at the console in caps before I
realize what I've done. Naturally, the command does
not work, because Linux/Unix is case-sensitive.

Although you can redefine the key in your
/etc/mykeys file with your favorite editor
(which would be a good idea if you also implement the previous hack),
here are two tricks you can use without having to edit any files.
This first trick simply disables the Caps Lock key for consoles so
that it has no function:

$ sudo echo "keycode 58 = VoidSymbol" | loadkeys

Some people like to convert the Caps Lock key into a Ctrl key. Here
is the simple command to do that:

$ sudo echo "keycode 58 = Control" | loadkeys

Again, if you want to have your computer make this change
automatically, see the sidebar Keep Your Custom Keys Intact for instructions.

keycode  59 = F1  F13 Console_13  F25
alt    keycode  59 = Console_1
control    alt    keycode  59 = Console_1