I would also add that 4.1 also ties into research UNIX v8.
On the VAX (via SIMH) its bootstrapped from a 4.1 system.
David du Colombier's guide uses the 4.1 image I found and modified with some 4.2 to get running on SIMH
Not having 4.1 would have made this far more involved. 4.2 is no doubt a major Internet milestone on the way to SunOS & 4.3 while 4.0/4.1 are important in a pre-tcpip focused world.
Naturally I'm biased into thinking they are all important, but I know resources /time are limited.
On Tue, Mar 12, 2019 at 2:22 PM +0800, "Nigel Williams"
<nw@retrocomputingtasmania.com> wrote:
On Tue, Mar 12, 2019 at 4:39 AM Larry McVoy wrote:
> Other than for history's sake, I don't see the value of 4.1
On the history side, I found having 4.1 BSD important when we were
recovering the build of a programming language on this version. As we
had the binary we wanted to be sure that when we re-compiled we could
confirm that the result was identical to the original. This was to
ensure that we had recovered the build environment as it was
originally. For that reason, I would urge preservationists to always
try to recover as many incremental versions as possible.