From mboxrd@z Thu Jan 1 00:00:00 1970 From: bqt@update.uu.se (Johnny Billquist) Date: Thu, 31 Jan 2002 19:51:41 +0100 (CET) Subject: [TUHS] Re: Porting Unix v6 to i386 In-Reply-To: <20020131102649.B19170@apple.ukc.ac.uk> Message-ID: On Thu, 31 Jan 2002, P.A.Osborne wrote: > On Wed, Jan 30, 2002 at 08:50:31PM +0100, Johnny Billquist wrote: > > On Wednesday 30 January 2002 10:18, P.A.Osborne wrote: > > > Having had a rummage and a chat with acolleague here at > > > UKC - it seems that V6 will be easier than V7, partially because > > > of the Lions commentary - but mainly because 286 protected mode > > > gives a very similar handling on memory management as the PDP did. > > > > What a silly argument. > > V6 and V7 both run on the PDP-11, so the memory > > management hardware used by them both are the same. > > Having looked through the source of v6 and v7 the comments are shall > we say minimalistic to people who are not as familiar with the PDP > architecture as say Ritchie and Thompson - ie ME! Hence the Lions > commentary makes life a darn site easier. > > I am not disagreeing with the second point you have made. However the > point is that V7 is a development on from V6 and the memory management > is more complex and thus requires more work. I thought I only made one point, and that was that the argument for V6 being easier to port because "286 protected mode gives a very similar handling on memory management as the PDP did". Since V6 and V7 both run on the PDP-11 it can absolutely not be an argument for preferring V6 to V7. Thus I think it is a silly argument. The rest is purely speculative on my behalf, and I really don't want to debate wether V6 or V7 would be better to port. I have a proper PDP-11 at home, and in addition, I run RSX, not Unix on it. :-) Johnny Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at update.uu.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol