Op Mon, 30 Jan 2012, schreef steve smithers:
Hans-Peter Diettrich wrote on Mon, 30 Jan 2012 17:40:27 +0100
Existing source code frequently assumes ASCII encoding. The obvious are
upper/lowercase conversions, by and/or or add/sub constant values to the
characters. It will be hell to find and fix all such code in the
compiler and RTL, even if only the constants have to be modified for
EBCDIC. Even code with the assumed order of common characters (' ' < '0'
< 'A' < 'a') has to be found and fixed manually - how would you even
*find* code with such implicit assumptions?
It does indeed. I am aware of the problems inherent in this. But the RTL
has to be more or less rewritten anyway to support OS. OS is a very different
animal to Windows or Linux.
If you try to achieve a port by modifying all code that deals with
characters you will fail. The amount of work becomes then far too big for
a single person, and the modifications become too huge and wide-spread
that you will raise objections for merging it with the SVN trunk.
In other words, do yourself a favour and keep ALL processing in ASCII. You
can convert between ASCII & EBCDIC on input/output. That way the
modifications in order to support EBCDIC are well concentrated in a single
piece of code, which can be easily merged without risk of destabilizing
the code base.
You can then use your manpower, and you still need *a* *lot* of it, to
write a code generator & RTL.
Daniël
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