#!/usr/bin/perl

open IN, "<bg.cnt" or die "can't open bg.cnt"; 
flock(IN,2); 
seek(IN,0,0); 
$cnt=<IN>;

close IN;

if ($cnt >= 3){
        $cnt = 0;
                }
else {
        $cnt = $cnt + 1;
     }

open OUT, ">bg.cnt" or die "can't open bg.cnt for writing";
flock (OUT, 2);
seek(OUT,0,2);

print OUT "$cnt \n";

close OUT;

@background=("corner.jgp","anduin.jpg","gandalf.jpg","ford.jpg");

print "Content-type: text/html\n\n";
print <<EndOfHTML;
<td background="images/$background[$cnt]">
EndOfHTML