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From: car@trux.UUCP (Chris Rende)
Newsgroups: comp.unix.questions
Subject: Unpolite daemons
Message-ID: <506@trux.UUCP>
Date: 11 Oct 90 17:19:24 GMT
Organization: Central Cartage, Sterling Hgts., MI
Lines: 33

[ System V Release 2 ]

I use the "-w" option to LP(1) to submit print requests so that I know when
they finish.

The trouble is, if I'm in the middle of typing a command line when the message
from "lp:" comes to my screen, what I was typing is lost!

I suspect that LPSCHED is doing IOCTL()'s to my tty in addition to WRITE()ing
the message. These IOCTL()'s probably have the effect of flushing the
input buffer. I haven't noticed this unpolite behaviour with programs such
WRITE(1).

Can anything be done to keep the input buffer from being flushed?
(Smart replies like "well, don't use -w with LP" are not welcome :-).

Ahhhhhh Multics:
Multics has a tty mode "polite" which would block/buffer output to the tty 
if you were in the middle of typing a command. After you press return, any
pending output would be displayed on the tty.

Multics has another mode "replay" which would allow output to the tty
while you are in the middle of typing a command. However, after interrupting
you with the output it would "replay" the conents of the input buffer to
your screen so that you could see where you were and continue on as if
nothing had happened.

car.
-- 
Christopher A. Rende           Central Cartage (Nixdorf/Pyramid/SysVR2/BSD4.3)
uunet!edsews!rphroy!trux!car   Multics,DTSS,Unix,Shortwave,Scanners,UnixPC/3B1
trux!car@uunet.uu.net          Minix 1.2,PC/XT,Mac+,TRS-80 Model I,1802 ELF
trux!ramecs!car     "I don't ever remember forgetting anything." - Chris Rende