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 Sandro Tosi, 07 September 2006

My keyboard, the Microsoft Internet Keyboard (don't shame on me, it was the cheaper, black keyboard...), has many special keys, that on Windows would allow to control Internet Explorer and some other aspects of the pc; but I don't have Windows, so I'd like to use those keys to control XMMS music players and maybe something else.

1. Special Keys

Using showkey you can find the code sent by every button on the keyboard. We are interested in the special one, so let's look at their code (I have an italian keyboard, so I'll translate the legend: maybe they won't be exactly the one on english version):

where "Press" means the code when the key is pressed, and "Release" the code when the key is released.

A similar output is available with xev; we report even that one since will be useful for the tools we'll use after:

2. Control special keys

There are a couple of tool to handle keyboard special keys

2.1 hotkeys

It's a really simple and customizable daemon to intercept hotkeys and associate to them a command/action.

Due to it's easy XML-enable configuration, I'll use this command XMMS. As a note, the Debian package already contains configurations for many multimedia keyboards, including Microsoft Internet I got.

2.2 lineak

It's another hotkeys daemon; if you're already using it, or what to try something different, you can try it and send me the configuration you've done :)

2.3 xbindkeys

With its companion xbindkeys-config it allows very easily to associate a command to a keys sequence. Sadly, it seems not to support special keys of my keyboard. This is its homepage.

3. How to control XMMS

There are some interesting options for XMMS, that let's you control it via CLI:

so, for example, calling xmms -f, we can play the next song in the playlist.

Some useful option is missing, for example volume management and the ability to go back/forward for the current song. There are some external tools that can be used to control XMMS far better (and many more not listed here):

• xmms-shell
• pyxmms
• pyxmms-remote
• xmmsctrl
• a Perl interface to control XMMS (it's a sort of shell) is available here

I've chosen to use xmmsctrl, a simple CLI tool with a huge control commands for XMMS (I maintain even the Debian package for it).

4. Control XMMS with hotkeys

Install xmmsctrl: you can install the Debian package, or take the source from author's site and compile/install by yourself.

Debian package for hotkeys provides a configuration file, /usr/share/hotkeys/msnet.def, for Microsoft Internet Keyboard. I've used that file to forge a config file to control XMMS.

To create that file, take the keycode from xev output when pressing a key; then you can create a file or copy an existing one in the directory $HOME/.hotkeys (that dir is local to the user who will execute hotkeys) calling the new file with a not-existing keyboard config (I chose msxmms.def). This is the file I use:

<?xml version="1.0"?>

<!-- Author: Sandro Tosi, matrixhasu@gmail.com, on 2006-09-07 -->

<definition>

  <config model="Microsoft Internet Keyboard">

    <userdef keycode="234" command="xmmsctrl time -5">Back 5 secs</userdef>
    <userdef keycode="233" command="xmmsctrl time +5">Forward 5 secs</userdef>
    <userdef keycode="232" command="xmmsctrl stop">Stop</userdef>
    <userdef keycode="236" command="xmms -t">Play/Pause</userdef>

  </config>

  <contributor>
    <name>Sandro Tosi</name>
    <email>matrixhasu@gmail.com</email>
  </contributor>

</definition>

Let's examine the line <userdef keycode="234" command="xmmsctrl time -5">Back 5 secs</userdef>, so that you'll be able to customize it more:

• userdef is the XML element to specify a custom key configuration
• keycode="234" is the code read from xev output for key press
• command="xmmsctrl time -5" is the command we'd like to execute when the key is pressed
• Back 5 secs is the text written in a box displayed when you press the key (in my box, at the bottom left of the screen; you can disable it with -o option)

Once you have the file ready to be used, you can execute this command:

$ hotkeys -t msxmms -Z

that sent the command in background, so you are ready to test the keys!

Since you have to execute the program before using special keys, I suggest to execute it at user login, placing previous command for example in $HOME/.bashrc.

Any comment is welcome!