! Make no mistake. The use of ISO-2022-JP DOES violate RFC 822.
! RFC 822 specifies ASCII. ISO-2022-JP, as you say, is NOT ASCII.
If ISO-2022-JP encoded Japanese character is violating RFC 822,
uuencoded Japanese charcter will also violate it, right?
How about uuencoded binaries like images or sounds?
I guess they are not ASCII.
In a strict sense no. The encoding result contains only
ASCII characters, however interpreting the contents is
another bag of problems. (822 does NOT say anything about
the contents structure -> there are a lot of different
ad-hoc structures around from the days before MIME.
Some mutually exclusive, or othervice not understood
elsewere.)
That is why using RFC-822 email with ISO-2022-JP does work
(it has a lot of track-record) however it does not mean an
email client without builtin support for it would understand it.
Displaying ESC-code plain in file is asking for trouble in my
mind. There have been a plenty of "letter viruses" when a
special ESC-sequence did some magic gymnastics with a terminal
(VT100 usually) and was thus able to send commands for the user
to execute without user being able to intervent -> most news
and email clients will NOT let any ESCs go thru to the display..
(Be paranoid, rather than sorry.)
Are they all illegal but acceptable because they will not cuase
problems?
It depends what you mean with "trouble". People reading
various *.binaries.* -groups USUALLY know what to do with
an encoded file, and how to open it, however as MIME usage
is not prevalent, there is no simple reliable automatic means
to process the articles. (Only dozens of ad-hoc systems..)
(I do know the NEWS-MIME isn't yet specified, but that is
another topic.)
Similarly when you receive email with uuencoded contents,
you have to know what to do with it, or have a really good
expert system handling your email (if you do, I would like
to know wherefrom to get it!)
Technically the RFC-822 just defined email in a format which
is similar to the one we are now using -- traditional manually
formatted email for human reading. Latter people thought
of ways of sending binaries via uuencode (and btoa, and ...)
What MIME created is STRUCTURE notation which can be used by
smart MUAs to analyze the email and pull out attached files,
switch character-sets, .. On overall give hints about the
processing.
// Satoshi
/Matti Aarnio <mea(_at_)nic(_dot_)funet(_dot_)fi>