if (eval { require IO::Compress::Gzip } ) {
	use subs qw (gzip);
	use vars qw ($GzipError);
	IO::Compress::Gzip -> import ( qw (gzip $GzipError) );
	$status = gzip "${FileName}" => "${FileName}.gz" or _error "gzip failed: $GzipError\n";
}
else {
	system qq[gzip -c ${FileName} > ${FileName}.gz];
}