ietf-822
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Re: Format=Flowed/RFC 2646 Bis (-02)

2003-11-18 10:13:42

In <2147483647(_dot_)1069075144(_at_)[10(_dot_)0(_dot_)1(_dot_)8]> Cyrus Daboo 
<daboo(_at_)cyrusoft(_dot_)com> writes:

OK - so that just goes to prove that there is no way to construct an 
inline-signed format=flowed messages such that it will be verifiable by 
both format=flowed aware and non-aware clients using the clipboard method 
unless the aware client copies the non-flowed text to the clipboard - which 
I think is wrong.

I think we are agreed that inline PGP signing will be understood by the
non-aware clients. What is now clear is that an aware client MUST have
some mechanism to make the un-re-flowed (i.e. on the wire) text available
to the user if he asks to see it. That might be dome by making the
Clipboard take the un-re-flowed version, or it might be done some other
way.

All this means is that we have to say format=flowed MUST 
NOT be used with inline-signed messages, otherwise there is no guarantee 
that an arbitrary recipient will be able to verify it.

But I still think that MUST is too strong. It is going to happen whether
you like it or not, so you have to warn of the dangers and give the aware
clients a mechanism to get around it.

| Which raises another issue. Mail clients which support format=flowed
| SHOULD put the original (unflowed) version of the text onto the Clipboard.
| IOW, you should be able to take the displayed text, put it into the
| clipboard (or dran'n'drop it), and plonk it into another (format=flowed
| aware) window, and it should automagically appear reflowed to suit the new
| window.

I think this is wrong. First off where are you going to find a 
format=flowed aware 'window' that is not in an email client? I want to be 
able to copy the flowed text from a message and paste it into a text editor 
or some other application and have it appear flowed.

If you plonk it into a window in an email client (say as part of
generating a new outgoing message) then it can be shown reflowed (but when
sent on the wire it will be as its 'true' self). I think if you plonk it
into a window that is not aware (e.g. into some editor) then it will show
up un-re-flowed (which is still a valid representation of the text). So
with my suggestion, ordinary unaware windows need do nothing with the
Clipboard than they did not do before.

But if copying the text of a flowed message to the Clipboard is going to
take it as it had been reflowed in the donor window, then you have to ask
exactly how it is supposed to appear. Is it just a text with lines of a
length as determined by the donor window and no trailing WS, or is it
still in a format=flowed form with trailing WS to show where it might be
reflowed yet again? Or is it just one long line of text for each
paragraph, in which case what about any quote marks in it?

I think these questions need to be addressed, though whether the standard
goes to the length of codifying the behaviours is another matter.

I just tried it using Opera (which is the only client I have which offers
format-flowed). When doing Copy/Paste from the compose window, it showed up
as one long line, but after it had been posted and read (it was a local news
article rather than an email), it behaved like a new format=flowed object.
I.e. at the point where it wrapped in the viewing window, the pasted
version showed a line end with a trailing SP (but it was longer than 76
characters, though). Is that the behaviour we typically expect?

BTW, it didn't do the right thing when pasted into a new compose window :-(.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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