Bitfields for device attributes (character device):
Bit(s) Description )
15 set (indicates character device)
14 IOCTL supported (see AH=44h)
13 (DOS 3.0+) output until busy supported
12 reserved
11 (DOS 3.0+) OPEN/CLOSE/RemMedia calls supported
10-8 reserved
7 (DOS 5.0+) Generic IOCTL check call supported (driver command 19h)
(see AX=4410h,AX=4411h)
6 (DOS 3.2+) Generic IOCTL call supported (driver command 13h)
(see AX=440Ch,AX=440Dh"DOS 3.2+")
5 reserved
4 device is special (use INT 29 "fast console output")
3 device is CLOCK$ (all reads/writes use transfer record described
below)
2 device is NUL
1 device is standard output
0 device is standard input
Note: for European MS-DOS 4.0, bit 11 also indicates that bits 8-6 contain a
version code (000 = DOS 3.0,3.1; 001 = DOS 3.2;
010 = European DOS 4.0)
SeeAlso: #01648,#01646