Re: Possible UTF-8 CJK Regressions in Terminal Emulators

[Kenichi Handa]

In article <address@hidden>, Stefan Monnier <address@hidden> writes:

> > As surrogate pair was not handled well by UTF-16 converter,
> > I've just fixed it too (not yet installed, I'm now adding
> > comments in a code).  Untranslatable characters are decoded
> > into UTF-8 form represented by the sequence of
> > eight-bit-graphic/control characters (the same way as UTF-8
> > decoding, thus we can use utf-8-post-read-conversion).  The
> > UTF-16 encoder encodes such a sequence back to the origianl
> > UTF-16 form.  So, now the UTF-16 support is at the same
> > level as UTF-8.

> Does that mean that some sequences of eight-bit-graphic/control are not
> encoded into the corresponding raw bytes?

No.  But, that's only the case that we encode a modified
text (i.e. eight-bit-graphic/control chars are
added/modified after we decoded a source).

> If so, that makes me a bit uneasy, since those special chars were
> introduced specifically to handle things like binary input or
> bad-byte-sequences and make sure that we at least preserve the raw bytes in
> those cases.

As far as we encode a non-modified text that is generated by
decoding a source, we can preserve the byte sequence even if
the original source contains bad-byte-sequence (for the case
of UTF-8, I found a case that doesn't work as expected and
fixed).

---
Ken'ichi HANDA
address@hidden