Paul Gilmartin asked:
> And why are terminal data sets ("DSN(*)") converted to
> upper case, no matter what I do?
and then provided an example of _data_ contained in a
terminal data set being folded to upper case.
Well, WHY is for the same reason I previously stated:
because TSO was written, in 1970, to operate that way,
and it has not been changed since -- not even when it
would have made sense to do so.
Why was it written that way? Terminals, such as the 3270,
naturally entered data in lower case (although they also
equally naturally displayed lower case characters as the
upper case equivalent). Lower case was "common" in data,
from the terminal, but not in data expected to be given
to programs (e.g., TSO commands) or written to data sets
or presented to I/O devices (such as printers). Somebody
had to convert all those "unusual" lower case characters
to upper case -- somewhere. For maximum utility (or so
IBM felt), they decided to do the translation in the most
common places where all or almost all the data flowed. At
the time, nobody objected. Lower case characters were a
very unusual thing. Virtually nobody had a TN train on
their 1403-N1 printer; if you did, your 1100 LPM printer
slowed down to become only a 200 LPM or less printer. No
standard terminal used with TSO (at the time, 3270s were
more expensive than a Cadillac with every option GM made
available) would display lower case. Lower case was not
needed, and not wanted. It just magically disappeared in
1971's TSO. Most folks were happy. But not all. Oh, well.
This behavior is (still) documented. For example, see the
TSO/E Programming Services SRL, chapter 8, where there's
extensive (and slightly silly, IMHO) documentation of how
the SAM interface macros work differently when the data
set is allocated to the terminal. It specifically states:
"Also, lowercase characters are folded to uppercase
characters."
"The data is folded to uppercase."
Thus that's just the way it IS, because that's originally
how it WAS. In other words: simply for compatibility with
1970-era programming and I/O equipment. This could have
been (and still could be) changed. Don't hold your breath.
--
WB
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
