Study Guide for Quiz 3 (23 Oct 2009)

You will be asked to write code for one of the following problems:

1) A registration form has a field for the username called "uname"
   and a field for the password called "pwd". Assume that the html
   code to create the form and a piece of JavaScript code to test
   the validity of the entries have already been written for you.
   On the server side the usernames and passwords are stored in a 
   file called "passwd"; one pair of username and password to a line,
   separated by a space. Write a PHP script that will check if the 
   username already exists in the file. If it does, it will write out
   "Choose another username". Otherwise it will append the username
   and password to the file and write out "Registration Successful".

2) Assume that there are two stylesheets - one for IE called "ie.css"
   and the other for all other browsers called "fx.css". Write a PHP
   script that will write out "Hello World" and link the "ie.css" if
   the client browser is IE and "fx.css" if it is any other client
   browser.

3) Instead of telling the client that he is the nth visitor, write a
   PHP script that will tell him that this is his nth visit. Keep the
   client IP address and number of visits in a file called "visits".
   Be sure to update the number of visits each time the client views
   that page.