Chapter 11

Figure 11 4. Bulletin board message search screen

A typical implementation might start with a structure like this, implementing 

just the listing, reading, and saving of new messages:

#!/usr/bin/perl

use CGI;

$query = CGI >new();  # instantiate CGI object

# determine what to do

if ($query >param("msg_id")) {       # user is reading to a message?

   do_read();

} elsif ($query >param("subject")) { # user is saving a message

   do_save();

} else {                             # list messages by default

   do_list();

}

# code for do_read(), do_save() and do_list() ...

The preceding code uses CGI.pm's param() method to examine incoming CGI 

parameters to determine what the user wants to do. Each subroutine called in the 

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