How to edit configurelines in new copied files upon registration

[celebx]

Hi!

I'm looking for a way to edit lines in new created (copied) files upon new user registrations for example:

$fp = fopen("$root_path/$account_lid/robboard.cgi","w");

   fputs($fp,fread(fopen("$root_path/standard/robboard.cgi", "r"), filesize("$root_path/standard/robboard.cgi")));

   fclose($fp);

   exec("chmod 777 $root_path/$account_lid/robboard.cgi");

Anyone knows how to access a file and edit specific lines in it?

Best Regards,
Snt