I get errors like this one:
Warning: fopen("http://fahhem.t35.com/usernames/fahhem.txt","a+") - Undefined error: 0 in /usr/home/freehost/26817/signin.php on line 2
when I open a file for reading.
I think we've already answered this:
You can open an http connection for writing! Use a relative path on the filesystem!
Well Fah hem... What you have to do is to go back to your PHP manual and "read" the chapter about fopen() again. Do not bother to "read AND write" in your manual. Just "read" it :-)
Happy coding /Andrin
