Walter Bright wrote:
Don wrote:
[1] What was size_t on the 286 ?
16 bits
Note that in the small memory model (all pointers 16 bits) it really
was possible to have an object of size 0xFFFF_FFFF, because the code
was in a different address space.
Not really. I think the 286 had a hard limit of 16 Mb.
I mean, you can have a 16 bit code pointer, and a 16 bit data pointer.
So, you can concievably have a 64K data item, using the full size of size_t.
That isn't possible on a modern, linear address space, because the code
has to go somewhere...
There was a so-called "huge" memory model which attempted (badly) to
fake a linear address space across the segmented model. It never worked
very well (such as having wacky problems when an object straddled a
segment boundary), and applications built with it sucked in the
performance dept. I never supported it for that reason.
A lot of the effort in 16 bit programming went to breaking up data
structures so no individual part of it spanned more than 64K.
Yuck.
I just caught the very last of that era. I wrote a couple of 16-bit
DLLs. From memory, you couldn't assume the stack was in the data
segment, and you got horrific memory corruption if you did.
I've got no nostalgia for those days...
