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Path: utzoo!mnetor!uunet!husc6!uwvax!umn-d-ub!umn-cs!randy
From: randy@umn-cs.cs.umn.edu (Randy Orrison)
Newsgroups: comp.unix.questions,comp.unix.wizards
Subject: telnet i/o redirection?
Message-ID: <4822@umn-cs.cs.umn.edu>
Date: 14 Apr 88 15:48:39 GMT
Reply-To: randy@umn-cs.UUCP (Randy Orrison)
Organization: Control Data
Lines: 40

System: Silicon Graphics running SGI Unix 3.5 (?)
	Silicon Graphics running ATT System V Release 3.2
I'm working on a project where we want to have a program talking to another
machine.  I'd like to be able to have the program open up a couple pipes and
the fork off telnet to do the talking, but simple experiments with telnet
are proving to be dismal failures.  I've tried the following approaches:
	cat - | telnet
	cat -u - | telnet
	telnet < /dev/tty
The first two result in telnet accepting the "open" command and connecting,
but then ignoring the rest of my input, until I hit the intr key when telnet
acts as if it were processing my past input at the telnet> prompt.  E.g.:
	% cat - | telnet
	telnet> open george
	...connected...

	Silicon Graphics (george)

	(nothing.... i type:  open george)
	(nothing.... i hit DEL)
	telnet> already connected to george telnet>
	connection closed
	%
(rough paraphrase).  The last one (telnet < /dev/tty) hangs up the console
and requires a reboot.

On the vax running 4.3 here, the first two do about the same things, but the
last works just fine.

I suspect that telnet is doing some ioctls that screw up pipes.  Does anyone
have any ideas what I can do?  Note that I need the solution for System V
so i don't have ptys available (always did like BSD better...).

Thanks for all you help!
	-randy
-- 
Randy Orrison, Control Data, Arden Hills, MN		randy@ux.acss.umn.edu
(Anyone got a Unix I can borrow?)   {ihnp4, seismo!rutgers, sun}!umn-cs!randy
What is a magician but a practising theorist?
		-- Obi-Wan Kenobi