Please go through the HTML Example before doing this example.

Create a sample perl file

  1. Using nano, we can create tutorial.pl:

    [username@l-lnx101 username]$ nano tutorial.pl

  2. Copy and paste the following code into your nano screen:

    #!/usr/bin/perl -w

    use strict;
    use Socket;
    my $remote_addr = $ENV{'REMOTE_ADDR'};
    my $iaddr = inet_aton($remote_addr);
    my $remote_host = gethostbyaddr($iaddr,AF_INET);

    print "Content-type: text/html\n\n";
    print "<html>\n";
    print "<head>\n";
    print "<title>Remote IP</title>\n";
    print "</head>\n";
    print "<body>\n";
    print "<p>\n";
    print "REMOTE_ADDR is $remote_addr.<br>\n";
    print "Lookup of $remote_addr is <b>$remote_host</b>.\n";
    print "</p>\n";
    print "</body>\n";
    print "</html>\n";
    exit;

  3. Save the file and go to http://webdev.cs.uiowa.edu/webdev/COURSEID/USERNAME/tutorial.pl where username is replaced with your hawkid. Unfortunately, this is old code and doesn't cope with IPv6.

  4. The page when viewed on l-lnx100 in the lab looks like:

    REMOTE_ADDR is 128.255.44.124
    Lookup of 128.255.44.124 is l-lnx100.divms.uiowa.edu