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====== Int 21H, AH=44H, AL=00H ======

===== Version =====

2 and higher

===== Brief =====

GET DEVICE INFORMATION

===== Family API =====


===== Input =====

        AX = 4400h
        BX = handle

===== Return =====

 CF clear if successful
            DX = device information word (see #01423)
            AX destroyed
        CF set on error
            AX = error code (01h,05h,06h) (see #01680 at AH=59h/BX=0000h)

===== Macro =====


===== 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
        this function was not supported by Digital Research's DOS Plus

Bitfields for device information word:
Bit(s)  Description     (Table 01423)
 character device
  14    device driver can process IOCTL requests (see AX=4402h"DOS 2+")
  13    output until busy supported
  11    driver supports OPEN/CLOSE calls
   8    ??? (set by MS-DOS 6.2x KEYB)
   7    set (indicates device)
   6    EOF on input
   5    raw (binary) mode
   4    device is special (uses INT 29)
   3    clock device
   2    NUL device
   1    standard output
   0    standard input
 disk file
  15    file is remote (DOS 3.0+)
  14    don't set file date/time on closing (DOS 3.0+)
  11    media not removable
   8    (DOS 4 only) generate INT 24 if no disk space on write or read past
          end of file
   7    clear (indicates file)
   6    file has not been written
  5-0   drive number (0 = A:)

===== See also =====

 AX=4401h,INT 2F/AX=122Bh, INT 29

===== Note =====

Text based on [[http://www.cs.cmu.edu/~ralf/files.html|Ralf Brown Interrupt List Release 61]]

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