You can request any URL you like via one of several methods:
First of all, you can use fopen() to open a URL if you include "http://" a..."
at the beginning of the filename. I have never actually done this, but I assume that the fopen itself performs the GET, so if you don't care about the data returned you probably don't have to read anything.
To open a URL and read everything from it, file("http://...") will read the requested page into its return value.
Finally, for a finer grain of control (e.g. you may need to follow redirects) you can open a socket to the URL, write the GET, and read the data back so you can see everything including the http headers.
