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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 ^
^ 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=[[en:docs:dos:api:int21:44:01|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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