[ale] Differences in UNIX & UNIX-like systems...

[Danny Cox]

On Wed, 2006-10-18 at 19:52 -0400, Jeff Hubbs wrote:
> I remember using emacs on my Amiga, which I obtained c. 1986-1987.  I
> knew at the time that it was a derivation of something from UNIX-land.

	Well, if we're going to tell old-fart war stories...

	I began using a Perkin-Elmer 3210 (about a VAX 11-750 class mini) in
the fall of '81, I think.  I found the emacs source posted to USENET,
collected all the pieces (remember when source was sent out in
pieces? ;-), and attempted to compile it.  Since this was a Perkin-Elmer
(nee Interdata 8/32), it didn't have alloca(), a BSD call which
allocated memory from the stack, so the compile failed.  I researched
alloca(), and then the mini's assembly, but no luck.

	Much later, around '86, we purchased a Pyramid running System Vr4,
which had all of the BSD-isms like job control, virtual memory (!),
networking, but no emacs.  Once again, I attempted to compile emacs for
that environment.  Emacs, as one of the last steps, will call an
unexec() function, which writes out the process memory into a file,
suitable for later execution.  It loads itself, does lots of
initialization, and saves itself.  Later, when that new image is
invoked, all the initialization is done.

	Pyramid used the new ELF/DWARF object format, and emacs didn't know
about that yet.  I did some research over a few days, and spent a
Saturday getting it to dump itself into a properly formed ELF
executable.  I learned a LOT about Pyramid's C library internals from
that trial.  That was emacs 18.26.something, I think, but that was long
ago ;-).

-- 
Daniel S. Cox
Internet Commerce Corporation