[comp.sys.ibm.pc] multiplex interrupt

nelson@sun.soe.clarkson.edu (Russ Nelson) (06/21/88)

According the Zenith's Programmer's Utility Package, Call 0 (Get
Installed State) of the Multiplex interrupt (2fh) *must* be defined
by *all* INT 2F handlers (their emphasis).

However, when I attempt to determine what mutiplex numbers are in
use by looping from 0 to 0ffh, my Z-386 running DOS 3.21 crashes
*when the program exits*.  Therefore, some multiplex handler doesn't
handle call 0 properly.  Does anyone know who, what, when, where, why
or how?