Category : C Source Code
Archive   : MSCHRT3.ZIP
Filename : 21.INT

Output of file : 21.INT contained in archive : MSCHRT3.ZIP
! BIOS interrupt 21h function list.
! Reference: MSDOS Functions Quick Reference Guide by Ray Duncan
! Microsoft Press ISBN #1-55615-128-4
! Note - all function numbers are in hexidecimal!
21 MSDOS System Services
00 terminate process
01 char input with echo
02 char output
03 aux input
04 aux output
05 printer output
06 direct console i/o
07 unfilt input no echo
08 char input no echo
09 display string
0A buffered keybd input
0B check input status
0C flush buffer & input
0D disk reset
0E select disk
0F open file
10 close file
11 find first file
12 find next file
13 delete file
14 sequential read
15 sequential write
16 create file
17 rename file
18 reserved
19 get current disk
1A set DTA address
1B get def drive data
1C get drive data
1D reserved
1E reserved
1F reserved
20 reserved
21 random read
22 random write
23 get file size
24 set rel record #
25 set int vector
26 create new PSP
27 random block read
28 random block write
29 parse filename
2A get date
2B set date
2C get time
2D set time
2E set verify flag
2F get DTA address
30 get MSDOS version
31 term & stay res
32 reserved
33 get/set break flag
34 reserved
35 get int vector
36 get drv alloc info
37 reserved
38 get/set country info
39 create directory
3A delete directory
3B set current dir
3C create file
3D open file
3E close file
3F read file/device
40 write file/device
41 delete file
42 set file pointer
43 get/set file attr
44 IOCTL functions
45 dup handle
46 redirect handle
47 get current dir
48 alloc mem block
49 release mem block
4A resize mem block
4B execute program
4C term proc w/code
4D get return code
4E find first file
4F find next file
50 reserved
51 reserved
52 reserved
53 reserved
54 get verify flag
55 reserved
56 rename file
57 get/set file date
58 get/set alloc strat
59 get ext error info
5A create temp file
5B create new file
5C lock/unlock file reg
5D reserved
5E get machine name
5F misc 3.1 functions
60 reserved
61 reserved
62 get PSP address
63 get lead byte table
64 reserved
65 get ext country info
66 get/set code page
67 set handle count
68 commit file
! end int 21h MSDOS System Services

  3 Responses to “Category : C Source Code
Archive   : MSCHRT3.ZIP
Filename : 21.INT

  1. Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

  3. But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: