INT 16 U - PCIBM PC Tools v8+ VSAFE - GET HOTKEY DISABLE FLAG
AX = FA04h
DX = 5945h
Return: CF clear
DI = 4559h
BL = hotkey disable flag (nonzero if hotkey disabled)
Note: this function is a NOP under VWATCH, merely returning CF clear/DI=4559h
SeeAlso: AX=FA00h,AX=FA05h