Difference between revisions of "Home and End keys not working"

Revision as of 17:46, 9 November 2012

Why do not my Home and End keys work in terminals?

Technically, this is a little wrong. Your home and end keys work fine in a terminal. They don't work, however, in your shell (bash).

Typically, command line applications use libreadline for interaction. If you know it does not use readline, this tactic may or may not work. For instance, ncurses applications most likely do not use libreadline, BUT ncurses is usually smart enough to map your Home/End keys properly.

libreadline problem

Usually applications are able to fix this on their own. The number one cause of this problem is setting your $TERM variable to something it is not in bashrc. All modern terminals are smart enough to set their own term variable.

Do not set $TERM manually. Let the terminal do it.

When in bash, do the following:

echo $TERM

You may or may not like the value it sets (i.e. 'xterm' when you want 'xterm-256color'). That is fine. Typically there is a way to configure your terminal to change this without changing the TERM variable.

For xterm and urxvt, it is in ~/.Xresources

XTerm*termName: xterm-256color
...
URxvt*termName: rxvt-unicode

For screen, you can set the $TERM variable in your ~/.screenrc with:

term screen-256color

TODO add more terminal configurations here

I do not touch my TERM value, and the keys still do not work right

This can happen. Not everything is covered 100% of the time. But libreadline had a workaround for this. libreadline maintains mappings for more obscure keys in /etc/inputrc (or ~/.inputrc for user-by-user changes).

If you look at the Arch /etc/inputrc, you will see the following lines:

"\e[1~": beginning-of-line
"\e[4~": end-of-line
"\e[7~": beginning-of-line
"\e[8~": end-of-line
"\eOH": beginning-of-line
"\eOF": end-of-line
"\e[H": beginning-of-line
"\e[F": end-of-line

All of these try to map your Home/End key values. To see the actual value of yours, you can use yet another libreadline binding, called "quoted-insert" which outputs the actual value of a key, rather than issuing the keypress. quoted-insert is typically "Ctrl-v". Let's try an example (done on urxvt):

Ctrl-v F6 outputs ^[[17~
Ctrl-v Ctrl-c outputs ^C
Ctrl-v Home outputs ^[[1~
Ctrl-v End outputs ^[[4~

For future reference, the ^[ is a literal (quoted-insert) Esc keypress. This means that these keys are actually sending "ESC [ 4 ~". In inputrc syntax, the ESC key is expressed with "\e" (as you can see above).

For example the urxvt keys shown above would be:

"\e[1~": beginning-of-line
"\e[4~": end-of-line

If your Home and End key values are not listed in /etc/inputrc (as you can see, with the ^[ to \e conversion, mine ARE listed), you need to add them there. 99% of the time this will not effect other terminals. Technically, one should add these settings to ~/.inputrc, because it's easier to keep track of, and stays with your user that way. You can also do MUCH cooler things with a user-specific inputrc (See Inputrc for more details).

Adjusting terminfo (If nothing helps)

• Do

  infocmp $TERM >terminfo.src

• Edit terminfo.src file in current directory to adjust keystrings. For example change khome and kend.

khome=\E[1~, kend=\E[4~, 

• Run

  tic terminfo.src

  This command creates ~/.terminfo directory
• Add

  export TERMINFO=~/.terminfo

  to your profile

Why do not my Home and End keys work in application XYZ?

If you've gone through the above, and your TERM is set properly, and your Home and End keys are properly entered into /etc/inputrc and ~/.inputrc, this is no longer system wide. Your keys are correct, but the application is not. You will have to consult the documentation for the given app on how to do this. Hopefully we can add some examples here as we come across broken applications.

Lynx

In lynx.cfg, use the quoted-insert characters above, replacing ^[ with \033:

setkey "\033[1~" HOME
setkey "\033[4~" END

URxvt/Rxvt

In your X resources (in ~/.Xresources file) you should add something like following:

URxvt*keysym.Home: \033[1~
URxvt*keysym.End: \033[4~

Zsh

See Zsh#Key_Bindings.

Less

Create file ~/.less with

$ lesskey -o .less -
#command
\e[4~ goto-end
\e[1~ goto-line

or for making less work in xterm

$ lesskey -o .less -
#command
\eOF goto-end
\eOH goto-line

or you may create systemwide config the same way.