Originally Published: Wednesday, 23 May 2001 Author: William Lynch
Published to: enhance_articles_desktops/General Page: 1/1 - [Printable]

Using Internet Keyboards with KDE

Dead keyboard? Want a new one anyway? Linux.com contributor William Lynch shows you the quickest way to get the new multimedia-enhanced keyboards working with Linux and your favorite applications.

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One of the last fading PC legacies is the 101-key keyboard, which is ever so gradually being replaced by the multimedia-enhanced keyboards known as "Internet Keyboards". Most major vendors of console hardware have copied this keyboard, which was initially popularized by Microsoft. The primary function of the Internet keyboards is to provide extra buttons for one-touch Internet applications and multimedia controls.

While many of the Internet features might be seen as nothing more than fluff, some of these additional buttons can be quite useful. For example, the author enjoys having a one-touch "mute" button for XMMS when answering the telephone. Similarly, the author has grown fond of the convenience provided by one-touch access to Google, especially when no web browsers are currently open.

How Do Internet Keyboards Work Under Linux?

The extra buttons afforded Internet keyboards work just like additional keys on the keyboard. The kernel keyboard driver picks these up just the same as any other keys. While it's an involved process, one could modify xmodmap for these keyboards and assign special events to each of the Internet buttons. However, thanks to a package called HotKeys by Anthony Wong, configuration of these extra keys is much easier. HotKeys is simply a system daemon that intercepts the scancodes of the extended buttons on these Internet keyboards and maps them to an event or application.

Installing and Configuring HotKeys

Hotkeys is an easy to install and somewhat straightforward to configure software package. Aside from a few quirks it also seems remarkably stable. This section will detail how to install and configure the HotKeys package for KDE.

Identifying Supported Keyboards
The following output from hotkeys identifies which keyboards are supported by the HotKeys software package:

[fwl@laptop fwl]$ hotkeys -l
Supported keyboards: (with corresponding options to --kbd-list or -l)
    acerwl      - Acer Wireless Keyboard
    btc9000     - BTC 9000
    itouch      - Logitech Cordless iTouch/Internet/Cordless Desktop
    kb9963      - Compaq KB-9963 keyboard
    kbp8993     - Chicony KBP-8993 keyboard
    mck800      - Process MCK-800
    msnatpro    - Microsoft Natural Keyboard Pro
    msnet       - Microsoft Internet Keyboard
    msnetpro    - Microsoft Internet Pro Keyboard
    mx1998      - Memorex MX1998 Keyboard
    mx2500      - Memorex MX2500 Keyboard
    mx3000      - Memorex MX3000 Keyboard
    polypix     - Polypix Keyboard
    sk2500      - Fujitsu/Logitech/Trust SK2500 Keyboard / Liteon-ak2500
    sk2501a     - Silitek SK5210A Keyboard
    sk2505      - SK-2505 Keyboard
    sk2800c     - SK-2800C
    sk7100      - Silitek SK7100 Keyboard
    sk9925      - Silitek SK-9925 USB Keyboard
[fwl@laptop fwl]$
Note: The author is using the Logitech Internet Keyboard (itouch).

According to the HotKeys documentation, Internet keyboards not listed here will probably work with the HotKeys software, provided the user maps out the keycodes into a keyboard definition file.

Package Dependencies
HotKeys requires only two packages to operate, libdb2 (maintained by Sleepycat Software and libxml ( the Gnome XML C Library). While libxml is available in binary form for most of the major Linux distributions, the source is also available. Since libxml is likely already installed on most Desktops, installation of this library will not be detailed here.

However, libdb2 needs to be of a specific version, 2.7.7, which may not be so widely available. The Debian distribution contains the original source code for this package which should compile on any distribution. The libdb2 package does not follow the standard installation method exactly, and it must be compiled in a specific manner. After unpacking and expanding the archive, perform the following steps:

[fwl@laptop db-2.7.7]$ ls
LICENSE       cxx/            db_printlog/    hash/        os/
README        db/             db_recover/     hsearch/     os_win16/
btree/        db185/          db_stat/        include/     os_win32/
build_unix/   db_archive/     dbm/            java/        test/
build_vms/    db_checkpoint/  dist/           libdb_java/  txn/
build_win16/  db_deadlock/    docs/           lock/        xa/
build_win32/  db_dump/        examples/       log/
clib/         db_dump185/     examples_cxx/   mp/
common/       db_load/        examples_java@  mutex/
[fwl@laptop db-2.7.7]$ cd build_unix/
[fwl@laptop build_unix]$ ../dist/configure
<output omitted>
[fwl@laptop build_unix]$ make
[fwl@laptop build_unix]$ su
Password:  <not echoed>
[root@laptop build_unix]# make install
Optional Features
As an option, HotKeys can utilize an on-screen display if the XOSD package from this site is installed.

HotKeys Installation
Now, the HotKeys package can be installed. Once the archive is unpacked, it follows the standard "configure, make, make install" procedure, except that the libdb2 installation directory may need to be specified with "--with-db2-inc=DIR" and "--with-db2-lib=DIR" where DIR is the directory where libdb2 has been installed.

Configuring HotKeys for KDE

While HotKeys is intended to be multi-user compatible, the multiuser configurations may not always work properly, although the software works fine for a single user configuration. The main configuration file for HotKeys is /usr/local/etc/hotkeys.conf which applies to all users, but a local .hotkeys in a user's home directory is supposed to override these settings. The author was unable to verify this feature successfully.

To configure HotKeys for KDE, the following changes must be made to the /usr/local/etc/hotkeys.conf file.

Kbd=itouch
WebBrowser=kfmclient exec /home/fwl
Email=kmail
Search=kfmclient openURL http://www.google.com
Note that the setting for Kbd may vary depending on the sort of keyboard in use, as showed in the previous section. The author uses the Logitech iTouch Internet Keyboard for this example. The other lines will open a file browser in the author's home directory, the kmail client and the Google search engine, respectively. The author's home directory needs to be explicitly specified because the HotKeys software lacks the ability to expand either the "~" or the "$HOME" shortcuts.

Next, it may be desirable to modify the keyboard definition for the keyboard in use. Be sure to backup the original keyboard configuration first. Then, edit /usr/local/share/hotkeys/Kbd.def. The author made the following modifications to the itouch.def file:

<VolUp        keycode="176" adj="1"/>
<VolDown      keycode="174" adj="1"/>
<userdef keycode="230" command="konsole %i %m">Konsole</userdef>

The author modified the value of "adj" to "1" to allow for a finer grained control for the volume settings. Also, the "Go To URL" button, signified by a running man on the author's keyboard, is redefined to its new action in this section, rather that in the hotkeys.conf file. The author has configured this key to open a Konsole terminal window when pressed.

Configuring HotKeys for Netscape

Unfortunately, Netscape does not lend itself towards HotKey's use as easily as Konqueror and KMail, partially due to bugs in KDE and partially due to the way the Navigator application functions. There are some workarounds for these shortcomings but integration is not as tight as it could be.

KDE Bug #21043
The KDE window manager kwin in KDE 2.1 has difficulties in communicating with the Netscape browser in the browser's "remote" mode. The "remote" mode allows a user to send input (such as a URL) to the currently running version of Netscape. In normal functionality, Netscape should be a able to identify the window ID of its current process, but kwin does not properly report this ID back to Netscape, resulting in the error message netscape: root window has no children on display :0.0. More information on this particular bug is available in the KDE bug report.

As a workaround, the ID of the current Netscape process needs to be sent to the Netscape command line when issuing remote requests. There is a diff to the /usr/bin/netscape start script located in the KDE bug report but it's malformatted due to word wrapping and may not work if there are vendor modifications to the /usr/bin/netscape script. As an alternative, one can create a quick wrapper script for the Netscape start script that will determine the window ID and pass it along to the Netscape remote command line. Copy the following script to /usr/bin/netscape-wrap.sh and change the permissions to 755.

#!/bin/bash
# A wrapper script for Netscape that passes the window ID to netscape
# Written 05.15.01 by FWL
ID=`xwininfo -root -all | grep Navigator | awk '{ print $1 }' | sort -r | head -
# Use the ID if netscape is already running
if [[ -n $ID ]]; then
        netscape -id $ID $@
else
        netscape
fi
exit 0
Additionally, since there is no way to start a Netscape mail client session from the command line, at least not as specified in the Netscape documentation, there is no clean way to start Netscape Mail without starting a new message composition. As a result, if the "Mail" key in the Internet keyboard is used with a running Netscape session, a lock error will occur. Similarly, if a Netscape Mail session is already running and the "search" or "homepage" keys are pressed, the Netscape Mail client will exit and a new instance of the browser will be launched.

Netscape Configuration
To configure HotKeys for Netscape, only the /usr/local/etc/hotkeys.conf file will need to be modified. After creating the /usr/local/netscape-wrap.sh script as described above, make the following changes to the /usr/local/etc/hotkeys.conf file:

WebBrowser=netscape-wrap.sh -remote 'openURL(http://www.yahoo.com)'
Email=netscape -mail
Search=netscape-wrap.sh -remote 'openURL(http://google.com)'
Note:The URL specified in the "openURL" can be any URL, though it should probably be configured identically to the browser's start page.

Conclusion

While the added functionality of an Internet keyboard may not be sufficient to warrant its own purchase, these keyboards are handy enough to warrant purchase when replacing a failed keyboard. Clearly, with the help of Anthony Wong's HotKeys software, the KDE desktop can take advantage of these extra Internet and multimedia keys.

About the Author
William Lynch is a technology consultant for Crave Technology in Denver, CO. He spends every waking hour either in front of a computer, practicing martial arts or watching hockey.





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