open (GZIPFILE, "$input_dir/$file") 
	|| warn "Can't open zip input file: $file: $!";
binmode GZIPFILE;
open (DATAFILE, ">>$input_dir/$dat_file")  
	|| warn "Can't open uncompressed data file: $dat_file: $!";
my $deflator = deflateInit() or die "Cannot create a deflation stream\n" ;
my ($output, $status);
while (<GZIPFILE>) {
	($output, $status) = $deflator->deflate($_) ;
	$status == Z_OK or die "deflation failed\n" ; 
	print (DATAFILE $output) ;
}
($output, $status) = $deflator->flush() ; 
$status == Z_OK or die "deflation failed\n" ; 
print (DATAFILE $output) ;