Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!apollo!weber_w
From: weber_w@apollo.COM (Walt Weber)
Newsgroups: comp.sys.apollo
Subject: Re: I hate to be a pain, but I need help with DM
Message-ID: <41a7cf1a.1b0ea@apollo.COM>
Date: 24 Feb 89 02:00:00 GMT
References: <11588@watdragon.waterloo.edu>
Reply-To: weber_w@apollo.COM (Walt Weber)
Organization: Apollo Computer, Chelmsford, MA
Lines: 33

In article <11588@watdragon.waterloo.edu> dvadura@watdragon.waterloo.edu (Dennis Vadura) writes:
>System:  DN 3500
>OS:	 SR 10.1
  [...stuff deleted...]
>Anyway, after staring into the 3 feet of documentation we have on Apollos here
>I see no mention of a termcap like capabilities description for DM windows.
  [...stuff deleted...]
>ie. PUT SIMPLY WHAT IS THE TERMINAL TYPE OF A DM WINDOW?????

Dennis :

The DM does not have any command sequences which can be embedded in the output
stream in order to control cursor positioning, display attributes, etc.  This
facility is offered through the vt100 emulator, as you already know.

Why??  The display manager, in creating/displaying windows, can be thought of
as mapping a portion of an underlying file into the display memory.  It is NOT
a terminal (or a pseudo-terminal), but a "view" of a portion of the underlying
file.  Responding to embedded control sequences to do "cursor positioning" under
this model of operation would be similar to requiring that file pointer seeks
be done by embedding escape sequences in write(2).  Remember, BOTH are operating
on files.  Thus, you gain the "infinitely scrollable transcript pads", but don't
have cursor positioning.  Under the vt100 emulator, you get the ability to
"clear screen", but give up the ability to reverse scroll the output window
to the beginning of the session.

Hope this helps.

...walt...
-- 
Walt Weber                            Apollo Computer          
(508) 256-6600 x8315                  People's Republic of Massachusetts
-The views expressed herein are personal, and not necessarily Apollo's-