use FileHandle::Unget;
  
my $fh = FileHandle::Unget->new(\*STDIN)
 or die "Cannot open filehandle: $!";

my $testline = <$fh>;;
$fh->ungets($testline);

print "$.: $testline";

for (my $i = 0; $i < 3; $i++) {
	$testline = <$fh>;
	print "$.: $testline";
}