🚀 go-pugleaf

Hope this is appropiate for comp.sys.sun since PC-NFS/Telnet is a (mostly)
Sun product.

OK, in a nutshell (?), here's the problem:

I'm running Telnet from PCs into an Accell (Unify) DBMS application on a
Sun.  Accell has this wonderful bug in which core is dumped on receipt of
a NUL (^@).

PC-NFS/Telnet has a (too?) perfect emulation of a DEC VT100: only 4
function keys (PF1-4).  However, we want to extend the number of function
keys.  Unemulated keys in Telnet send a NUL when pressed: BOOM ... SIGSEG.

A commercial PC macro-expander (ProKey), has an undesirable interaction
with Telnet, in that it occasionally send a NUL while typing -- a nuisance
at best; at worst, BOOM ... SIGSEG.

I wrote a resident macro expander which seems to work fine, until Telnet
is invoked, at which point an expanded function key (say 'F1' -> '^[[OP')
seems to be buffered somewhere until an un-macro'd key (say 'h') is hit --
then everything comes out.  This TSR uses BIOS INT 16H (key
request/status).

Finally, the question(s):

What interrupts does PC-NFS/Telnet use to trap keystrokes?

How does one override dynamic interrupt vector grabbing?

Any (other) commercial PC products tested with this type of setup?

It seems that Telnet dynamically invokes a file called ME.COM, the
terminal emulator I presume, which then grabs hold of a number of BIOS and
DOS interrupts, effectively overriding any other TSR programs.

By poking around in ME.COM I seem to find that this emulator uses hardware
interrupt 09H (keystoke), BIOS interrupt 16H (key/status request), and a
few DOS INT 21H subfunctions -- not to mention about a hundred others. :-)
Do I have to grab hold of all these vectors to get this beastie to work,
and then dynamically override attempts by other software to get hold of
and swap these vectors?  Sheesh!

Tom.
P.S. Reply by E-mail.  I'll summarize if enough interest.
-- 
Tom Poage, UCDMC Clinical Engineering, Sacto., CA
ucdavis.ucdavis.edu!sunny!{poage,root,postmaster,news}
ucbvax!ucdavis!sunny!{poage,root,postmaster,news}