JavaScript/XUL in Mozilla, etc.) so a universal language independent approach 

would make a lot of sense. This is where DCOP and D BUS come into play, but 

in contrast to the embedded scripting language approach they face the problem 

with IPC/RPC.

Desktop interprocess communication

DCOP is the standard KDE Desktop Communication Protocol and can be used 

for all kinds of KDE desktop automation and scripting purposes. It is based on 

the Inter Client Exchange (ICE) protocol and uses UNIX sockets instead of 

remote calls. As with D BUS (which is the corresponding GNOME approach and 

hosted by freedesktop.org), it has its roots in a CORBA implementation but was 

completely redesigned for desktop needs since the KDE developers where not 

happy with the CORBA performance at that time. The GNOME developers 

sticked to CORBA (with their optimized ORBit2 implementation) but added 

D BUS to their toolkit (for example, for hardware event notification).

On an even higher level ,you can use Web services to integrate applications, but 

the Linux desktop itself provides much more efficient tools like DCOP and D BUS 

to communicate with your applications. Let us take a closer look at DCOP since 

this is a proven KDE technology that can also be used for KDE applications 

running on the GNOME desktop.

DCOP

When you log into your KDE session a program called 

kdeinit

 is started (by 

startkde

). It triggers other applications like 

dcopserver

 and the KDE daemon 

kded

, which are responsible for system configuration management and caching 

(syscoca), inter process communication, and a lot more. If you really want to 

understand how this process works and which environment variables and 

configuration files can influence it, you should read the

 KDE for System 

Administrators Guide

 available at:

http://www.kde.org/areas/sysadmin/

You can now explore your desktop environment and make DCOP calls with the 

command line tool 

dcop

, its graphical counterpart 

kdcop

, or with the DCOP 

language bindings for Perl, Python, Ruby, Java, etc., which are part of the 

kdebindings 

package. The 

dcop

 command syntax is as follows:

dcop [ application [object [function [arg1] [arg2] [arg3] ... ] ] ]

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Linux Client Migration Cookbook   A Practical Planning and Implementation Guide for Migrating to Desktop