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To: Terry Lambert <terry@lambert.org>
Cc: msmith@atrad.adelaide.edu.au (Michael Smith), bde@zeta.org.au, dgy@rtd.com,
        hackers@freebsd.org, helbig@mx.ba-stuttgart.de
Subject: Re: wd driver questions 
Reply-To: Jason Thorpe <thorpej@nas.nasa.gov>
From: Jason Thorpe <thorpej@nas.nasa.gov>
Date: Mon, 17 Mar 1997 20:26:04 -0800
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On Mon, 17 Mar 1997 19:25:36 -0700 (MST) 
 Terry Lambert <terry@lambert.org> wrote:

 > > My current 'favorite' is the NetBSD libsa, which has all of the bits
 > > that I need, modulo perhaps some more network drivers, however it doesn't
 > > appear to have all of the "wonderful" ELF stuff that you keep raving
 > > about.
 > 
 > I've never raved about ELF in NetBSD... not even in their boot code.

...So, for the record, NetBSD's libsa doesn't have a generic ELF loader
in it yet because not all architectures use ELF.  Currently, the MIPS-based,
Alpha, and PowerPC ports do (although I haven't committed the PowerPC
stuff yet).

The trick is backwards-compatibility, i.e. retaining the ability to load
both kinds of formats, and that means footprint.  The NetBSD/alpha boot
blocks currently support loading ECOFF and ELF formats, for example,
because, until just recently, ECOFF was the standard format.

I think this will be changing soon, however.  Now that the FSF has a sane
way of saying "This ELF binary is for this OS", I've put the following on
my NetBSD/hp300 TODO list:

	- grok ELF symbol tables in DDB

	- write ELF loader for libsa

	- make ELF work on NetBSD m68k

...but it's not a priority right now... too many other things to do :-)

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
Moffett Field, CA 94035                                Pager: 415.428.6939