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archivesHow to have home and end keys working in xterm and in the Matlab command line.
My home, end and delete keys were not working in my unix terminal (xterm) or in my Matlab console. For instance in the Matlab console (Matlab run in –nodesktop mode), all I was getting after pressing the home or end key was 4~ or 5~, same was going on for the terminal (xterm and csh). As most shells recognize the ctrl+a, ctrl+e, ctr+d shortcuts for home (beginning of line), end (end of line) and delete and as Matlab too recognizes these shortcuts, the simplest solution is to have your keys sending these shortcuts when in a terminal. You probably do not want to completely reconfigure your keys as they might be working fine in text editors.
To configure your keys simply add this to your /home/user/.Xdefaults file:
*VT100*Translations: #override \
<Key>Home: string(0x01)\n\
<Key>End: string(0x05)\n\
<Key>BackSpace: string(0x08)\n\
<Key>Delete: string(0x04)\n\
~@Num_Lock<Key>KP_Home: string(0x01)\n\
~@Num_Lock<Key>KP_End: string(0x05)“string(0x01)” means to send the code 0x01 which is the ASCII code for ctrl+a. “string(0x02)” would mean ctrl+b, “string(0x05)” indeed means ctrl+e etc.
A list of ASCII control code can be found here : http://www.phanderson.com/C/ascii.html
(Btw, If someone can explain me why the fist ASCII code is ctrl+a and not simply a I would be impressed).
How to test the configuration
To load the .Xdefaults file enter:
xrdb -merge ~/.XdefaultsTo check the state of your X configuration:
xrdb -queryTo test your configuration, it is also often useful to check which code a key sends. To do this, in a terminal, just press ctrl+v then press the key. The code sent by the key should appear, for instance ^a (=ctrl+a) if you pressed the home key or directly ctrl+a.
[Edit]
Also it is important that you know which terminal and shell you are using. To know this:
echo $SHELL
echo $TERMBonus
As a bonus here are a few more configurations:
To be able to use page up, page down to scroll in xterm:
*VT100*Translations: #override \
<Key>Prior: scroll-back(1,halfpage) \n\
<Key>Next: scroll-forw(1,halfpage)To be able to use the wheel mouse to scroll in xterm:
*VT100*Translations: #override \
<Btn4Down>,<Btn4Up>: scroll-back(1,halfpage) \n\
<Btn5Down>,<Btn5Up>: scroll-forw(1,halfpage)To configure your function keys for often used commands:
*VT100*Translations: #override \
<Key>F1: string("ls") string(0x0d) \n\
<Key>F2: string("ll") string(0x0d) \n\
<Key>F3: string("ps") string(0x0d) \n\
Shift<Key>F1: string("ls -lg") string(0x0d) \n\
Shift<Key>F2: string("pwd") string(0x0d) \n\
Shift<Key>F3: string("ps -ax") string(0x0d) Notice that 0x0d is nothing else than the ASCII code of carriage return.
To get autocompletion thanks to your history in the command line. That is you press a few characters then you press up and it will complete the line with the last command with the same beginning in your history. With this, it is useful to have a long history and the same history file for all your opened terminals.
If you use tcsh, put this in your ~/.cshrc file:
# 5000 last commands are saved
set history = 5000
# All terminals merge their history in one file
set savehist=(5000 merge)
if ( $?tcsh ) then
bindkey -k up history-search-backward
bindkey -k down history-search-forward
# inser to backward-delete-word
bindkey ^[[2~ backward-delete-word
# Prompt with the current path
set prompt="%~>"
endi“if ( $?tcsh )” checks that the current shell is tcsh.
If you use bash add this in ~/.bashrc (or /etc/inputrc):
# up & down arrow keys
"\e[A":history-search-backward
"\e[B":history-search-forward\e means escape key. Escape key also sometimes appear as ^[. So if you press ctrl+v then up arrow you will get ^[[A.
Notice that once you have correctly set up the home, end keys and the up, down keys for history you will have the same configuration between xterm and Matlab.
All this should pretty much work under UNIX or LINUX. However, with all the configurations around (Linux,Unix,HP-UX,Unix through exceed/csh tcsh/gnome,KDE,CDE,etc.) a few things might not work in your configuration. So good luck!
Posted in Linux | 5 comments | atom
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Thanks. Any way to have this work on gnome-terminal btw? It doesn’t seem to use same translations and a Google search did not show up anything…
Thanks Misha
Well, I am using most Unix/CDE and Linux/KDE. So unfortunately I do not know much about Gnome.
As a try, let me know your shell (echo $SHELL) and terminal (echo$TERM). I’ll see if I can figure out something.
Also use and abuse of what I say in the “Test your configuration section”. That is verify your xrdb -query, and verify which codes your keys send and post this here.
Thank you. Here is my relevant output:
misha@misha-d630:~/Montague Lab/code$ echo $SHELL
/bin/bash
misha@misha-d630:~/Montague Lab/code$ echo $TERM
xterm
misha@misha-d630:~/Montague Lab/code$ echo $COLORTERM
gnome-terminal
It seems clearly a gnome-terminal problem though, as I try in xterm using the Ctrl-V Home and Ctrl-V end, and I get:
misha@misha-d630:~$ ^A^E
If I try in gnome-terminal, I get:
misha@misha-d630:~/Montague Lab/code$ ^[OH^[OF
I did a little googling on this question, and the only reply I saw that seemed relevant was people’s advice to look at gnome-terminal source…
Thank you Misha
First, you need to put 2 spaces at the end of your lines to go to the next lines (I know it is not obvious ;-) ). It is Markdown syntax. I have done it for clarity.
Then, what about using xterm? If it works in xterm, use xterm. Nope ?
To have it working in gnome-terminal, you need to find where the code for your home key is set up. If it cannot be changed then I do not have any other solution than using xterm.
Thanks for that, worked for me too. Only had to say
XTerm*VT100.translations:
instead of
*VT100*Translations:
in .Xdefaults? No idea what the difference really is.