Contents of the BU4DIR.DOC file
This program will display a dos-style direcotory of a DOS 4.01 Backup disk
from the CONTROL.nnn file on the disk.
It takes one parameter, the drive on which the backup disk resides, generally
A: or B:. The colon can be omitted: BU4DIR A will also work.
The output can be redirected to a file, or piped thru MORE, for better output.
The source code is inlcuded. While I reserve the rights to the source, I am
releasing the program into the public domain. This program must be distributed
with the source file and this document file. No fee may be charged for this
program, other than nominal fees charged by users groups and the like.
If you modify the source code, please give send a copy to:
1515 Jeff Davis Hwy #208
Arlington VA 22202
Any donations you feel compelled to send will not, of course, be refused.
Following is the file structure of the CONTROL.nnn file:
CONTROL.nnn File Header: [first part of file, not repeated]
1 Length of file header (byte) [including this byte] always 139
2-9 BACKUP (followed by 2 blank spaces
10-11 This disks' disk number (word) [matches nnn of CONTROL.nnn]
Path Header: [repeated for every path after file desc for previous path]
1 Length of Path Header (byte) [including this byte] always 70 (F)
65-66 Number of files in this path (subdirectory) (word)
67-70 Offset to beginning of next path (dir) entry in this file (long int)
File Desc [repeated number of times indicated in path header]
1 Length of File Desc (byte) [always 34]
14 End of filename indicator (?) Always Ascii (a heart)
15-18 File size (long int)
19-20 Disk no. that this file starts on. (word)
21-24 Offset to this file's data in BACKUP.nnn data file. (long int)
25-28 Bytes on this disk. [always file size unless split] (long int)
29-30 File Attributes (word)
31-34 DateTime of file (long int)