open DATABASE, $Rawdata or die "opening $Rawdata: $!\n";

##</code><code>##

use Fcntl qw(:flock);
flock DATABASE, LOCK_SH or warn "Couldn't obtain shared lock: $!\n";

##</code><code>##

  my $q = CGI->new( $param_string );
  foreach my $key ($q->param()) {
    my $value = $q->param($param);
    # ...
  }