sub search {

	my ($file, $searchString) = @_;

	local *F;
	open(F, "<", $file) or return 0;
	binmode(F);

	my $nbytes = read(F, my $window, 2 * BLOCKSIZE);

	while ( $nbytes > 0 ) {

		if ( $window =~ m/$searchString/ ) { close(F); return 1; }
		
		$nbytes = read(F, my $block, BLOCKSIZE);
		last if $nbytes == 0;

		substr($window, 0, BLOCKSIZE) = '';
		$window .= $block;
	}

	close(F);

	return 0;
}