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D-Bus is a message bus system, a simple way for applications to talk to one another. It provides a simple yet powerful interprocess communication (IPC) mechanism.
The D-Bus allows programs running in the same computer to interact with each, no matter the programming language (Perl, Python, Java, C/C++, etc). It provides a daemon that coordinates all interaction between different services and can start services on demand.
This talk shows how to use D-Bus with Perl.