[segmneted memory]
> Then you're back to the horrendously inefficient DOS stuff: You have
> to carry around two registers to do one pointer.
For a huge memory model, yeah. As it stands you DO actually need 2
registers, it's just that only one segment gets used for userspace under
Linux.
> To get the common
> stuff fast, you probably want to increment just the low end of the
> pointer. This means that you get restrictions on sizes of arrays.....
> Anyway, DOS flashbacks. The whole muck!
Yeah, it's not the best, but I cannot think of a single better solution
to large memory space using 32 bit pointers.
> Don't even think about it.
Well, it does get around the problem of addressing more than 2 (or 3) GB
of memory under Linux; this will cost something somewhere. mmaping only
part of the file is the other option and is IMHO uglier, especially if I
need access to more than 3GB simultaneously; the segment model does make
that possible, if a little difficult.
> I knew pretty quickly after I got my 640K
> XT, that I really didn't want to bother with those issues. It is also
> the main reason that I'm a Linux user since 0.12 or something like
> that.
Segmentation for everything is bad. Segmentation where relevant is
useful. It's that nice balance that is so hard to achieve...
Daniel
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