layers vs SunView (was: Will X Windows be standard part...)

[Doug Gwyn]

In article <5400018 at snail> carroll at snail.CS.UIUC.EDU writes:
>1. You can telnet out of a SV window. Telnet hangs in a layer.

I think you must have a pretty sick implementation of layers
and/or telnet.  Telnet works fine for me from a layer, using
either xt or pty based implementations.

>2. You can have about as many SV windows as you want. Only 6 layers.

7 on the 630, plus optionally 7 more if you decide to use the second
port for host access instead of a printer.  A layer on the 630 can
also split into sublayers, and layers that don't need host access
can detach themselves, freeing the channel for use with another layer.

I find in practice I seldom use the 6th layer on my DMD (5620),
just as most of the Sun users I've seen have a whole pile of idle
icons that they practically never access.

>3. You may belittle speed, but waiting 7 or 10 minutes for layer program
>   to load is very irritating.

I imagine it would be!  However, it doesn't take 7 or 10 minutes for
anything I know of to download.  That would be around 500KB at 19.2KB
(assuming your computer is streams-based, or otherwise good enough to
push the packets at that rate), which is much larger than any DMD
application I know of.  Remember, the whole idea is that only the
special interactive portion of an application runs in the terminal;
most of the file management etc. runs on the host.  The default
terminal emulator (shell) takes no time at all since it's resident;
typical applications take from 10 seconds to a minute at 9600 baud,
but then with any planning you started the download while you were
still occupied with work in another layer.

If you're talking about downloading over a 1200 baud phone line,
then for fairness you should consider a diskless Sun trying to use
the same facilities for its Net Disk.  (I don't think it's even
supported.)  If you think the Sun should be configured standalone
(with disk), then for fairness you should consider the 630 with an
attached 3B2 and disk, or some other comparable set-up.

>4. Being able to icon-ify windows in SV is wonderful...I can put things that
>   that I don't need all the time in  little icons, and grab them when they
>   are useful.

Layer processes can also be designed to do that.  I have one..
But they usually aren't, due to difference in philosophy and
in operating environment.  Indeed, although they appear
similar, due to both having bit-mapped displays and both
(typically) having a UNIX on tap, the difference in environment
is quite visible to the programmer.  Depending on what you want
to do, one or the other might be the best fit; neither is
universally superior.

>5. "toolplaces" in SV : this lets me set up my windows the way I want,
>   without having to calculate screen positions.

The .layers (or .mpxrc) file specifies initial layer windows and
processes.  Somehow I don't have much trouble with calculations,
given that 1 inch = 100 pixels.

>6. When you exit a shell in a SV window, the  window closes. In layers, it
>   just sits there, unusable.

Wrong; if you have a sensible host multiplexer ("layers" utility),
termination of the host process (often, but not always, a shell)
attached to a layer channel will cause the layer to be deleted, and
vice-versa.

>7. Support programs. The  SunView support is vastly superior, such as
>   the icon editor, font editor, mail, etc.

The DMD has had an icon editor for many years now.  I admit that a
font editor would be useful.  There is undoubtedly some wonderful
software available for either display type that is not available
yet for the other.  AT&T's poor marketing of the DMD did not help
layers software availability.

Sorry to go on at such length, but with both a Sun and a 5620 on
my desk (and a 630 nearby) I thought a more balanced appraisal
might be appropriate.