I seem to recall reading a thread some time ago where someone had researched a very small footprint bootable floppy where they used tricks like an older version of DOS for less memory use and hexing out unnecessary data from files to keep disk usage to a minimum.
Does anyone know if this was a thread somewhere on VOGONS and where it might be?
I also don't remember exactly if the goal was the smallest memory footprint or disk space footprint (most likely the later).
I did some tests on the various DOS versions I have available in my DBDOS
package, and found:
1PC-DOS 0.90 2 3 files, 10702 bytes of 144524 bytes disk 3PC-DOS 1.00 4 3 files, 11551 bytes of 142549 bytes disk 5PC-DOS 1.10 6 3 files, 13279 bytes of 146337 bytes disk 7PC-DOS 2.10 8 3 files, 39552 bytes of 334027 bytes disk 9PC-DOS 3.00 10 3 files, 58926 bytes of 318437 bytes disk 11PC-DOS 3.30 12 3 files, 77566 bytes of 1402553 bytes disk 13PC-DOS 7.1 14 3 files, 140576 bytes of 1366949 bytes disk 15MS-DOS 1.12 16 3 files, 13097 bytes of 301488 bytes disk 17MS-DOS 2.11 18 3 files, 40800 bytes of 335028 bytes disk 19MS-DOS 3.31 20 3 files, 79555 bytes of 1399996 bytes disk 21MS-DOS 4.00 22 3 files, 108314 bytes of 1383253 bytes disk 23MS DOS 5.00 24 3 files, 118669 bytes of 1383528 bytes disk 25MS-DOS 6.22 26 3 files, 133557 bytes of 1375749 bytes disk 27FREEDOS 0.84 28 2 files, 112289 bytes of 1410019 bytes disk 29CALDERA OpenDOS 7.01 30 6 files, 336483 bytes of 1173366 bytes disk 31PTSDOS 6.51 32 3 files, 120659 bytes of 1378322 bytes disk 33WindowsME DOSboot 34 3 files, 209785 bytes of 1338053 bytes disk
"bytes disk" is the free-space shown by DIR + the sizes of the files.
This will not include some "hidden" files as well as any overhead (Boot
sector(s), FATs, Dir entries etc.)
The 1.xx versions were on 160k diskettes
Middle ones are on 360k
and later are on 1.44m
To get anything useful, you will have to add whatever you wish to run.
I've made a pretty capable ImageDisk bootable setup which include ImageDisk
itself, a number of useful tools including full ability to move images off/on
via Network, Serial or Parallel, and dozens of common "packet drivers" to
enable network access. - All on a single 1.44m(3") or 1.2m(5.25) diskette.
I swapped the io.sys onto a boot disk and it complained that it couldn't find command.com (which was on the disk). I used the command.com that the GitHub project provided instead, but then I got errors about drive letters, even after setting LASTDRIVE=Z in config.sys. Maybe I'm doing something wrong, but couldn't make it work right as a drop-in replacement for a boot disk.
