INT 60 - INTRSPY/CMDSPY v1.0 only - API

Program: INTRSPY is a script-driven debugger included with the book
	  _Undocumented_DOS_.
InstallCheck:	determine that a) the handler is an IRET instruction, and
	  b) the signature 0Dh "INTRSPY vN.NN" immediately precedes the handler
Notes:	INTRSPY will hook the first available interrupt in the range 60h-67h.
	If INTRSPY is installed, the DWORD immediately after the IRET stores
	  its entry point (see #03275)
	INTRSPY v2.0 (included with the second edition of the book) no longer
	  supports this API
Index:	installation check;INTRSPY