HFISCHER@USC-ECLB.ARPA (08/15/84)
From: Herm Fischer <HFISCHER@USC-ECLB.ARPA>
The problem mentioned with PC/IX is a hardware problem with the PC.
PC/IX has some programs which get very upset when the async ports
fail to provide interrupts. (Most programs which use the ports
have some kind of timing mechanism, or signal/alarm which takes
care of the port not returning interrupts.)
My personal PC/XT, purchased from the first lot IBM made, never has
this problem, except when the modem is unplugged or whatever. (I
have had PC/IX on it for 2 1/2 months!)
My company has a half-dozen PC/XTs, recently purchased, and of
very obviously poorer quality control, and some of them have
very painful problems with the interrupts. One machine worked
for six hours to then crash dead on PC/IX, because (with much
pain and suffering) we discovered that iterrupts on tty0 were
mucked all up.
If you have problems with "loggers which refuse to die" on shutdown,
ports which work poorly, or the like, GET YOUR PC FIXED. The
repair guys are not familiar with interrupt driven software, so
expect a real hassle explaining why PCDOS works and PC/IX doesn't.
Also check for a strange problem I have seen where the /dev/tty's
have a use count greater than one. If you find that, remove the
offending /dev/tty and re-mknod it.
Herm Fischer
-------