On 10/10/23 22:22, Grant Taylor wrote:
On 10/10/23 3:15 PM, Rick Troth wrote:
The copy-n-paste point makes me wonder if the fonts are actually
mapped to ASCII values.
I was wondering the same thing.
I'm watching the thread to learn more.
*blush*
Gotta be prepared to say "I was wrong".
I don't know graphical environments well enough to analyze it. But it
would mean that, yes, there *is* A/E translation happening even in
the graphical 3270 emulators. (In hopes of not steering Juan wrong
with what I said before.)
I would have naively assumed that the A/E translation is happening
between the TN3270* protocol and the in memory screen buffer.
This would mean that the buffer can be displayed with any font the
user chooses /and/ it would more cleanly support copy / paste.
*I actually assume that similar would happen with communications using
more traditional SNA on the LAN; e.g. DLC. -- If memory even
remotely serves after a long day.
A/E translation is a challenge on several fronts.
One is that DBCS and Unicode don't relate at all (as encoded).
When I first sank into this swamp, circa early 1990s, there was a
valiant effort, prominently visible at SHARE in those days, to resolve
mappings of the myriad 8-bit code pages.
Most terminals in my shop were CP37. The best table we could come up
with mapped "CP37v2" to ISO-8859-1. (This, of course, did not serve the
CP500 fans nor the ISO-8859-other for 2, 3, and so on.) I still
reference that table.
Tom Brennan might remember some of this saga. *:-)* Translate tables
abound! VM TCP/IP has more than I could keep straight in my head.
CP37v2 was a customer invention that fixed the square brackets problem
in CP37. As far as IBM was concerned, there was no CP37v2 ... *but* ...
IBM came out with CP1047 which edged closer to CP37v2. CP1047 is the
official code page (I was told) for USS. CP1047 is the official code
page of a certain ISV product I was involved with in recent years, one
where character sets are crucial.
Over on the ASCII side, ISO-8859-1 was the norm for all Unix systems
that I encountered, including Linux. But then Unicode landed on our
planet. Linux embraced it, using UTF-8, so did other platforms. That's
all fine and good until we want to talk to an EBCDIC system, either by
way of 3270 emulation or via SSH.
The web burst onto the scene. Thankfully HTTP and HTML have tagging
capabilities, so for most consumers ... well ... they have no idea the
work the techies have gone thru.
-- R; <><
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN
