The Linux keyboard driver

Use loadkeys to change the code produced by the BackSpace key from Delete to BackSpace:

% loadkeys
keycode 14 = BackSpace

Assign the string “emacs\n” to the function key F12, and “rm *~\n” to Shift-F12 (the keycode 88 was found using showkey; the F66 is a random unused function key symbol):

% loadkeys
 keycode 88 = F12
 shift keycode 88 = F66
 string F12 = "emacs\n"
 string F66 = "rm *~\n"

Create the compose combination that will compose | and S into $:

% loadkeys
 compose '|' 'S' to '$'
 compose 'S' '|' to '$'

Reset to some default state:

% loadkeys -d

After the above handling, the obtained character(s) are put in the raw tty queue. Depending on the mode of the tty, they will be processed and transferred to the cooked tty queue. (Don't confuse raw mode as stty knows it, with the raw scancode mode discussed above.) Finally, the application will get them when it does getchar();.