HelpPC 2.10	Quick Reference Utility	Copyright 1991 David Jurgens
INT 21,19 - Get Current Default Drive        AH = 19h        on return:        AL = current default drive (0=A,1=B,etc)        - determines the current default drive
Esc or Alt-X to exit	int 21,19	Home/PgUp/PgDn/End ←↑↓→