[comp.unix.aix] the 3270 is not a terminal

rcd@ico.ISC.COM (Dick Dunn) (09/27/89)

People have been talking about the 3270 and how AIX (and UTS) have some
awkwardness dealing with it.  I think it would be a lot more fair to soft-
ware folk to turn this around and say that the 3270 has trouble dealing
with UNIX.  The 3270 is NOT a general-purpose terminal.  It can be used
for certain classes of transaction entry, and it's got some spiffy
features that make it work nicely for that.

But it's also designed to some archaic hardware tradeoffs--the most pain-
ful being that transmitting to the host machine locks the keyboard.  This 
makes it inherently unsuitable for any sort of fine-grained interaction.
Because of this, it imposes a model which is no longer generally accepted
and which is pretty hostile--namely that in a dialog between human and
machine, the machine completely controls the progress of the dialog.  That
assumption is so fundamental to the way the 3270 works that you can't do
much about it.  Probably the best use of a 3270 with a UNIX system would be
as barter for a real terminal.
-- 
+---------+     Dick Dunn    rcd@ico.isc.com    ico!rcd      (303)449-2870
| In this |         4th annual MadHatterDay [10/6/89]:
|  style  |            A Thousand Points of Madness
|__10/6___|

brian@lcc.la.Locus.COM (Brian Horn) (09/29/89)

	Well, actually the 3270 console CAN be used as a general purpose
terminal under AIX, INCLUDING running such programs as vi.  However, I would	state that it is truely only for the masochistic.  (I've done it :-()
The way you deal with the idiot box being a block mode device is that whenever
you want what you have typed so far to actually be sent, you must type PF12.
For vi this generally means one character, PF12, next character PF12, until
you get really good at anticipated what the screen will look like after you
send your commands typed in so far.  (Sigh, technique for using a 3270 under	Unix?).
	As far as 3270 type terminals OTHER than the console, forget it.
It was deemed not a priority, though, who knows, IBM may change their
collective mind.

							Brian Horn
							PMTS AIX development