I am trying to intercept intrinsic calls from a native mode program by
writing my own routine and placing it in an XL.  I have done this trick
in the past with compatibility mode programs using SPL to write the
routine and placing it in an SL.  I would then patch the executable and
change the name of the intrinsic called to be my new routine.  This is
the same trick MPEX uses when they "hook" a program.  My problem is that
I can't get this to work on a native mode program.  I write my new
procedure (I've tried "C" and Pascal) and put it in an XL and patch the
executable to call the new routine.  When I run my patched program with
XL="XL" I get the infamous "unresolved external".  I suspect that the
problem has something to do with the fact that the program is calling an
intrinsic and my routine is not "defined" as an intrinsic.  I can't put
my routine in the system XL.

How can I write a routine in "C" or Pascal that is defined as an
intrinsic and will be found by a program calling an intrinsic?

Thanks for any help.

Keith Fortner
Hewlett Packard, Atlanta
Information Technology Engineer
(404)648-7011,  Telnet 648-7011