Posting variables to a cgi without a form

Hey all, What is the best wat to post some variables to a cgi file and capture the output so I may strip out all the html tags, I want to replace a forms action with a php script which will mimic a forms post method, allowing me to better format the response, as at the moment the cgi is written in c and creates a whole html page which i need to strip back down to text before I can include it in my site. I know about the string and filesysytem functions, sort of looking for a quick example of passing the variables to the cgi and capturing the output. Any help much appreciated, Regards, Joseph