Category: non-traditional input devices
Flags: Undocumented function
INT 21 - PenDOS PENDEV.SYS - ???
AX = 4403h
BX = file handle for device "$$PENDOS" or "$$PD_REG"
CX = size of buffer
DS:DX -> buffer containing ???
Return: CF clear if successful
CF set on error
AX = error code (01h,05h,06h,0Dh) (see #01680 at AH=59h/BX=0000h)
Program: A limited version of PenDOS by Communication Intelligence Corporation,
which provides pen capability to keyboard-based programs, is bundled
with IBM DOS 6.1
Note: this call sets the WORD at offset 1Ah into the device driver request
header used to call the driver to 0000h.