How Possible is This?

I know using XML it's possible to create a Ground Maneuver Camera System (GMCS); however I would like to do this using C. Does anyone know if this is possible? Is there a way to access the KEY_ functions through C? I suppose if hard pressed, I would be willing to learn how to do the gauge in XML as long as it could communicate to the master control (which will be in C). For the most part, to me XML looks like Sanskrit written by a junkie in the midst of withdrawal... Any help would be appreciated.Matt