[comp.arch] ABI vs. POSIX

hutch@fps.com (Jim Hutchison) (01/13/90)

In <18132@umn-cs.CS.UMN.EDU> mike@umn-cs.cs.umn.edu (Mike Haertel) writes:
>I don't see how ABI is related to "open systems."

It doesn't, it's just an agreement for applications to play the same games
on different machines without having to be "ported".

>Source level compatibility ought to be enough for anyone.  With the
>emergence of, e.g., ANSI C, POSIX.1, and (less desirably) the
>X window system, it will be substantially easier to write portable
>programs, and these standards are likely to have a far longer viable
>life than any ABI.

Common languages, system interfaces, and window systems are things which
make porting easier, to be sure.  They do little to help you spread your
product over a wide range of machines.  Compatibility == chance to sell.

>I see source level standards as being far less likely than ABIs
>to kill future innovation.  RISC architectures, and surely the
>SPARC, are far from the last word in computer architecture!

ABIs kill innovation?  Hmm, let's look at this closely.  We have ANSI C,
which gives a standard language (maybe outdated in 10 years).  Then we
have POSIX.1 which is a standard which will grow-or-die with the needs of
its community.  Along with these we have the ABIs for various architectures,
which will grow in number with new architectures, or die out as a bad-fad.

I see ABI as being a nice little flag to 'cc' which you can tell it to make
and ABI application instead of an application which has your whizbang fpa
instructions, or XXX-special instructions.  The advantage of this being
that you can support multiple machines/vendors with a single executable.
You don't get the max performance you get out of a nicely tuned program
either, but it runs right off of the shelf.

Hey, but that's just me looking at a way this could work out for the best.
It could be a really annoying twisted little way of keeping us all down on
the farm while Sun takes off and designs new compliers and new hardware. :-)

--
/*    Jim Hutchison   		{dcdwest,ucbvax}!ucsd!celerity!hutch  */
/*    Disclaimer:  I am not an official spokesman for FPS computing   */