#!/usr/local/bin/perl

  print "Content-type: text/html\n\n" ;

# Initialize files and random number
  @files = ( "a.htm", "b.htm");
  $logfile = "/log-directtory/experiment.log";
  srand(time ^ $$);
  $num = rand(@files);

# Print Out Randomly Chosen File
  open (HTML,"<$files[$num]") || die "Failure to open HTML File" ;
  while () { print $_ ; }
  close (HTML);

# Log Event
  open (LOG, ">>$logfile") ;
  $date = `date`;
  chop $date ;
  print LOG $files[$num], " ", $date, " ",
            $ENV{"REMOTE_ADDR"}, " ", $ENV{"REMOTE_HOST"}, "\n";
 close (LOG);