Special characters in linux
by KyuOne of the (minor) recurrent problems i ever had with linux involves special characters such as é, è, à, ç and so on using my QWERTY keyboard. Indeed, as someone who must very often type in french, these characters are almost vital! 
Having been raised the windows way of doing this (alt + 130 power! 
) I was totally lost on how to do this in linux. after almost a year though, i finally discovered there was a rather quick and easy way to do this: the Compose key.
First of all I will try to explain the concept of this compose key. To put it simply, It’s a key that you can use to combine symbols and create special or accented characters that are not on your keyboard.
For instance, on my keyboard, the left winkey is set as compose key. thus by pressing [winkey] then [’] and [e], i get an é. similarly, [winkey] [=] [e] gives the euro sign €.
please Note that these keys are to be pressed one after the other (unlike the traditional ctrl+alt+delete for example )
Now, ready to set that compose key? let’s go, i promise that will be real quick :P
First open your terminal and open your xorg.conf
$ Sudo nano /etc/X11/xorg.conf
Please feel free to use any text editor (graphical or otherwise) here, i just chose nano to be more accessible irrespective of specific WMs
This should open your xorg.conf file, which contains configurations for most graphics related operations as well as your mouse and keyboard.
To set your compose key you should look for the section on keyboard within this file. in my case it looks like this:
Section “InputDevice”
Identifier “Keyboard0″
Driver “keyboard”
Option “CoreKeyboard”
Option “XkbRules” “xfree86″
Option “XkbModel” “pc105″
Option “XkbLayout” “us”
EndSection
Here, you just have to add a new line
Option “XkbOptions” “compose:lwin”
just before the endsection. (i have chosen the lwin key personally. you can replace it with anything like lalt, lctrl rctrl etc )
if your xorg.conf already contains a line starting with “Option “XkbOptions” ” (for example “Option “XkbOptions” “lv3:ralt_switch”) all you have to do is to add a comma and the mapping for the compose key inside the second double quotes (which in my example would give something like “Option “XkbOptions” “lv3:ralt_switch, compose:lwin”) i don’t know if i’m being clear here, just ask in the comments if you do not understand :P
here we go now just save the file, restart x, and your compose key should be up and running :P
And oh, before i forget, here you can find a list of key sequences with the compose key
enjoy, and if there are any queries, the comment form is here :P
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