Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!cica!tut.cis.ohio-state.edu!husc6!m2c!chansw!chan
From: chan@chansw.UUCP (Jerry H. Chan)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Dell and Dell 386SX feedback sought
Message-ID: <1442@chansw.UUCP>
Date: 9 Mar 90 07:24:37 GMT
References: <670004@hpfcmgw.HP.COM> <2146@sunquest.UUCP> <511251@nstar.UUCP> <1014@upaya.lilink.COM>
Organization: Chan SmartWare Computers, Worcester, MA
Lines: 72

In article <1014@upaya.lilink.COM>, tbetz@upaya.lilink.COM (Tom Betz) writes:
> Quoth larry@nstar.UUCP (Larry Snyder) in <511251@nstar.UUCP>:
> |
> |We have VP/ix here at nstar - and use it daily to run a DOS based BBS
> |under Interactive Unix (2.02) without problems.  As a matter of fact,
> |the 386/ix release of VP/ix has run every DOS application that I have
> |tried.
> 
> [comments about WP5.0 / WP5.1 not working]
> Beware of any program that insists upon writing temporary files
> to the C: drive.  Other than that, any DOS program should work
> just fine.

To be fair, the problem described above only applies if attempting to
run several simultaneous sessions from the same virtual drive ala
networking. Running WP5.0 (I haven't tried 5.1, but don't expect any
problems) works *fine* under VP/ix in "standalone" mode.  Similar issues
apply to running standalone apps under a network environment, i.e.,
Novell (the great red hack ;-).

Besides the problems running protected mode software under VP/ix, the only
other problems I have noted are

	* Running sw which relies on clock tics (i.e., many games) -- SW
	  will run extremely sluggish, since VP/ix simulates these

	* Running Windows-286-based apps (you tend to get "Unable to emulate
	  2-byte instruction" errors and trap out of VP/ix back to Unix
	  (still a problem as of R1.1.1)

	* Printing tends to be extremely slow, being that there is an
	  additional level of indirection (DOS app prints using BIOS
	  interrupts which are simulated, i.e., read, SLOWER; these BIOS
	  interrupts are intercepted by VP/ix to output the data to a
	  temporary file; the DOS app must complete printing before this
	  temp file can be closed and shipped off the the Unix print
	  spooler).  Better off printing directly to a file and printng that
	  file directly to the Unix spooler if possible).

	* Software running on a 386/20 seems to behaves as if it's running on
	  a 286/8 (my subjective estimate), even on an unloaded system.

	* You are limited to a 10M virtual drive, of which you may have up
	  to 2 (C: and D:) without going to a separate physical DOS partition.
	  There may be a way to create larger virtual drives using mkfs on a
	  Unix file (theoretically), but I haven't experimented.  Sure, you
	  can put lots of data on the Z: drive (Unix filesystem), but
	  there's a fair amount of software with anti-network hooks built-in
	  so that you can't run stand-alone SW on networks (i.e., Ventura 2.0)
	  w/o buying a network version.

	* Running VP/ix on serial terminals comes with it's own class of
	  problems -- remapping ALT, CTRL, SHFT, etc. key combinations as
	  well as function keys, running apps which expect 25 lines on the
	  screen instead of the typical 24 lines on terminals (unless you're
	  running the newer class of PC-emulating tubes, i.e., Wyse 60's),
	  etc., etc...

	* VP/ix currently only emulates DOS 3.3, not DOS 4.0+ (did I
	  overhear somebody say that this was a blessing in disguise ? ;-)

My view of VP/ix is that it's a security blanket of sorts allowing a user
to make the transition to Unix more easily by letting him carry some of the
old DOS baggage via VP/ix (IMHO).  I wouldn't get too comfortable there
though, given its limitations.

[ Absestos gear donned... flame away 8-) ]
-- 
Jerry Chan 508-853-0747, Fax 508-853-2262  |"My views necessarily reflect the
Chan Smart!Ware Computer Services & Prods  | views of the Company because
Worcester, MA 01606                        | I *am* the Company." :-)
{bu.edu,husc6}!m2c!chansw!chan             \---------------------------------