* \brief Registers a function as the default main function of processes.
*
* Registers a code function as being the default value. This function will get used by MSG_launch_application() when there is no registered function of the requested name in.
* \brief Registers a function as the default main function of processes.
*
* Registers a code function as being the default value. This function will get used by MSG_launch_application() when there is no registered function of the requested name in.