> Mouse, do you have a tool to put sun3 boot blocks on a disk from
> other machines?

No, at least, no custom tool akin to sunlabel.

> Will Netbsd/Sparc's installboot do the trick?

Maybe; it wouldn't surprise me if it did, but it also wouldn't surprise
me if it didn't.  It reads the a.out file at least to the extent of
picking a symbol out of the symbol table to know where to stuff the
list of block numbers.  The filesystems are the same endianism between
sparc and sun3, so that's not a problem, but I don't know whether the
a.out formats are sufficiently compatible.  You may get an instant "bad
magic number", it may work, or it may mysteriously fall over....

If you were to cross-compile the sun3 installboot with the sun3 header
files, generating a sparc executable, that would stand a much better
chance of working.  You may find you need to link with a similarly
cross-compiled libc though, which would be a pain.

As a possibly related note, when I was playing with NetBSD/sun3 on one
machine that at one point had SunOS 3.5 on it, I did find that I could
boot from a disk with

- SunOS 3.5 bootblock in sectors 1-15
- SunOS 3.5 second-stage booter in /boot
- NetBSD ufsboot in /ufsboot
- NetBSD kernel in /netbsd

by telling the SunOS booter to boot ufsboot.  The SunOS booter was
unable to load the NetBSD kernel, apparently because it's just too big
(I think the SunOS /boot can't load anything over a meg).  But telling
SunOS /boot to load ufsboot and then telling that to load netbsd seemed
to Just Work.  (Of course, this assumes a SunOS-3.5-compatible UFS
filesystem on that partition.)

If you "mv ufsboot vmunix", it might even all work without human
intervention, though I didn't try that - I was doing testing and
development on that machine and never wanted to do this unattended.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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