XML to c data parser

Hi everyone. My requirement is very simple. i need to send a value say int a =900 to xml editor in inkscape. i need to get the value there in xml. thats it. actually i need to know how to connect xml editor in inkscape to c code. only bid if you know how to do this. you can also search and let me know the right approach. more details will be provided to the person who will succeed to do this. this is a very big project. you just have to do a small part to indicate that you are the right person. Write 'rastdd' in the start of your bid to make sure that you have read the details. low bids will be preferred.