On 11/8/2017 12:02 PM, Noel Chiappa wrote:
From: Jon
Forrest
In the early days of Unix I was told that it
wasn't practical to write a
pager because such a thing would have to run in raw mode in order to
process single letter commands, such as the space character for going on
to the next page. Since raw mode introduced a significant amount of
overhead on already overtaxed machines, it was considered an anti-social
thing to do.
Something sounds odd here.
I agree, now that I think about it. I do remember being told not to
write such a thing, due to the load it would cause. Maybe John Nagle,
who had the cube next to mine, might remember better.
Overhead was definitely an issue with EMACS on
Multics, where waking up a
process on each character of input was significant. I think Bernie's Multics
EMACS document discusses this. I'm pretty sure they used the Telnet RCTE
option to try and minimize the overhead.
I remember ~40 students at UCSB trying to run 'vi' on a Vax 780 with 4MB of
RAM. Between the lack of memory and the overhead of raw mode, it wasn't
a pretty sight.
Jon