Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!mailrus!tut.cis.ohio-state.edu!cwjcc!hal!ncoast!allbery
From: allbery@ncoast.UUCP (Brandon S. Allbery)
Newsgroups: comp.unix.wizards
Subject: Re: Interactive Background Processes
Message-ID: <12078@ncoast.UUCP>
Date: 1 Aug 88 21:59:57 GMT
References: <8029@alice.UUCP> <1988Jul13.001105.29472@gpu.utcs.toronto.edu> <1280@csuna.UUCP> <1988Jul19.223111.3644@gpu.utcs.toronto.edu>
Reply-To: allbery@ncoast.UUCP (Brandon S. Allbery)
Followup-To: comp.unix.wizards
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 34

As quoted from <1988Jul19.223111.3644@gpu.utcs.toronto.edu> by woods@gpu.utcs.toronto.edu (Greg Woods):
+---------------
| Since I didn't want to go in to the requirements for implementing all of
| these things, I tried to make a simple statement.  I didn't want to
| consider things like homemade PTY or SXT drivers and such.  USUALLY a
+---------------

Are add-ons to SVR2 as made by various resellers exempt from this?  Because
they can easily lead to the same situation:  vendor X adds ptys but not
job control, and voila! emacs has interactive subprocess windows.

I have my doubts that layers can be used for emacs unless ptys can be
multiplexed they way terminals are -- of course, to be orthogonal with ttys
controlling ptys *should* be able to be multiplexed....

+---------------
| system that has the "facilities" [system calls / drivers] for
| implementation of such features will also have some user-level commands
| for exploiting these facilities, ie. shl will be there if you have
| sxt's, and systems with pty's [nice for emacs] will ususally have
| job-control facilities built into the shell as well.  BTW: Emacs may
| still not work with interactive processes on systems that have no PTY's
| or Streams, or multiplexed I/O.
+---------------

While layers requires sxt's, there is no requirement that ptys and job
control go together; I have seen systems with job control but no ptys and
systems with ptys but no job control.

I think you're trying to argue for the use of "pure" Unix (AT&T or BSD), in
which case you must absolutely hate what Sun and AT&T are doing to your pure
Unicen right now....  ;-)
-- 
Brandon S. Allbery, uunet!marque!ncoast!allbery			DELPHI: ALLBERY
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