Int 21 Fn 4400  - DOS 2+ - Ioctl - Get Device Information                  [D]

   AX = 4400h
   BX = handle

Return: CF clear if successful
       DX = device information word (see below)
       AX destroyed
   CF set on error
       AX = error code (01h,05h,06h) (see AH=59h)

Notes: value in DH corresponds to high byte of device driver's attribute word
     if handle refers to a character device
   Novell NetWare reportedly does not return a drive number in bits 5-0
     for a disk file

See Also: AX=4401h,INT 2F/AX=122Bh

Bitfields for device information word:
 character device
  bit 14: device driver can process IOCTL requests (see AX=4402h)
  bit 13: output until busy supported
  bit 11: driver supports OPEN/CLOSE calls
  bit  7: set (indicates device)
  bit  6: EOF on input
  bit  5: raw (binary) mode
  bit  4: device is special (uses INT 29)
  bit  3: clock device
  bit  2: NUL device
  bit  1: standard output
  bit  0: standard input
 disk file
  bit 15: file is remote (DOS 3+)
  bit 14: don't set file date/time on closing (DOS 3+)
  bit 11: media not removable
  bit  8: (DOS 4 only) generate INT 24 if no disk space on write or read past
       end of file
  bit  7: clear (indicates file)
  bit  6: file has not been written
  bits 5-0: drive number (0 = A:)