$n = read($r, my $lf, 1);
defined($n) or die "read final byte of cat-blob failed: $!";
die "bad read on final byte: <$lf>" if $lf ne "\n";
$n = read($r, my $lf, 1);
defined($n) or die "read final byte of cat-blob failed: $!";
die "bad read on final byte: <$lf>" if $lf ne "\n";