EMT and IOT instructions

[estes at tty3b.UUCP]

Thanx for the numerous replies for my request for information about IOT
and EMT signals.  Many persons (~7) wrote to say that EMT stood for
"emulator trap" and IOT stood for "I/O trap".

In the meantime, I caught one of my errors using sdb (as several people
later recommended).  For those who are interested, I was moving a program
from a VAX running 4.1bsd to a 3B20S running UNIX 5.0 and to a PDP 11/70
running UNIX 4.0.  I got the EMT trap on the 3B, and the IOT on the PDP 11,
with two different programs.  (I had two different problems, both of which
I caused as I was trying to compensate for differing system calls.)

Thanx once again to all of you for the rapid and numerous responses.

Ted Estes
Teletype Corp., Skokie, IL
{we13, otuxa}!tty3b!estes