Posts for Tag: haskell

XMonad - quickstart and intro

XMonad is a minimalist Window Manager written in Haskell. There are plenty of pretty screenshots of various xmonad setups on the net, but as a newbie it's not clear how to use them or how to get started. Say you find yourself in the  XMonad/Config archive page and find a pretty looking screenshot like NNoel's (below):

You install XMonad, update your .xinitrc, restart X and this is what you actually see:

It's a little intimidating to be confronted with this, and it's really tough to know how to go from "I have a blank screen" to "check out my shiny desktop". There's no easy way to get to a Settings/Configuration menu to customise things, and clicking around achieves very little indeed. Even firing up a web browser to google for some guides isn't very obvious. 

I recently went through this whole process, and managed to piece together a nice simple xmonad config. This is a guide to how to go from blank screen to a setup like the below:

We've got a status bar which shows handy things like workspaces, info about any active network interfaces, the usual cpu/memory usage shenanigans, volume (from a slightly hacky script, more on that later) date and the weather where I am. Also the little Tux emoji in the corner is clickable - by default it saves a screenshot of the whole screen, but you can customise it pretty easily since it's just executing a command in the shell.

To get this sort of setup we first need to make sure a couple of fonts are installed - Source Code Pro and Font Awesome. You could just run the commands below, but if you want could find the latest release of Source Code Pro on this page in case there's any updates:

    $ curl -LO https://github.com/adobe-fonts/source-code-pro/archive/2.010R-ro/1.030R-it.tar.gz
    $ tar -xzf 1.030R-it.tar.gz
    $ git clone https://github.com/FortAwesome/Font-Awesome
    $ sudo cp source-code-pro-2.010R-ro-1.030R-it/TTF/*.ttf Font-Awesome/fonts/*.ttf /usr/share/fonts
    $ fc-cache -f -v

Now we can install the necessary packages that we need:

    $ sudo apt-get install xmonad xmonad-contrib xmobar dmenu cabal-install
    $ cabal install xmonad-extras

Finally we can pull down my xmonad config from github

    $ cd && git clone http://github.com/smcl/xmonad .xmonad

Now all the packages are installed, and the Xmonad config is all setup we can restart X and should see something like this

Still a blank screen, but now we have a little status bar. To start with we can bring up an xterm by hitting Windows-Shift-Return:

Obviously from xterm we can launch whatever app we want from here, like firefox:

We can close windows using either some app-specific functionality (Ctrl-Q in firefox, or typing "exit" in xterm), but you can also close the current selected window from XMonad by holding down Windows-Shift-C.

Launching your apps from an xterm could be a little inconvenient, and the terminal itself could fill up with diagnostic messages unless you remember to redirect stderr to /Dev/null each time. 're squeezed side-by-side it's not ideal, plus your xterm will fill up with all sorts of fun diagnostic messages. A better way to work is to launch them using dmenu - a program we installed earlier that let's us launch applications from within monad easily. To bring up dmenu hit Windows-P, if you start typing it'll attempt to autocomplete programs from your PATH:

I tend to use workspaces to organise my windows - so I'll have firefox running on its own in one, then a couple of xterms in another, emacs on its own somewhere else etc. To create a new workspace and switch to it press Windows-1, Windows-2 ... Windows-9. If you're in, say, workspace 1 and you want to move the current window to workspace 2 you can his Windows-Shift-2.

The location used for the weather status is hardcoded in ~/.xmobar/xmobarrc. It's decided by the first arg to "Run Weather" - in my case I've used LKTB, which is the ICAO code for Brno airport. Find your nearest airport's ICAO code using this page and find/replace both instances of LKTB (there should be two) in the file.

Now that the irritating part of XMonad is out of the way, you can see what else you can do by checking out the XMonad tour or take a look at the cheat-sheet below and experimenting. 

I'd also recommend fiddling around with ~/.xmonad/xmobarrc (documentation is here) adding new items to the status bar. Particularly the "Run Com ..." which let's you run arbitrary commands and will display whatever the output was . The reason it might look a little odd is that it's written in Haskell, so you might want to spent a little time with the excellent Learn You A Haskell to get familiar - but honestly you could get pretty far just copy-pasting existing lines and tinkering with them.