Generating a php file

Hi there I am trying to generate a php file, which has variables that i need to have in it ie $_SERVER but not actually be parsed as they need to be in the actual script. I also need to send some variables to assign values to other variables in the script. How is this possible ? I have tried placing the contents of the script within a string, but all the variables gets parsed, and the super globals cause an error. Let me know .