🚀 go-pugleaf

Hi Windoze Programmers:

In the owl/examples directory in BC++ 3.1 (3.0 also) there is a sample
bitmap display program call bscrlapp.cpp.  In this file they make use
of a "magic" identifier called "__ahIncr", apparently to step from the
end of one segment to the beginning of the next in a large block of
memory obtained from GlobalAlloc().  There is a cryptic message about
Windows doing something funny to this symbol.  Other than this one use
of __ahIncr and a single line "__AHINCR  size = 0" in
/windows/system/import.lst, I can find no other mention anywhere.  I
did a global grep in the /borlandc and /windows directories.  I also
looked in several Windows programming books that I have, but none
mentioned it either.

Does anyone have any more information about this symbol (or another
also in import.lst "__AHSHIFT")?

Also, from reading Petzold, I understand that if I have allocated a
very large block using GlobalAlloc() (>64K bytes), then I cannot use a
huge pointer and step from byte 0xffff to 0x10000 by simply adding 1.
There is some magic about protected mode and adding 8 to the segment
register that is not clear.  Any ideas?

BTW, I am trying to write a program to read and manipulate large
(640x480x256) tiff files.

			Thanks, Ralph
-- 
G. Ralph Kuntz
Medical student, UMDNJ - Robert Wood Johnson Medical School, Class of 1994
kuntz@umdnj.edu			(H) 908-463-7170
[Computer scientist for Bell Labs in a former life (before Med. School)].