D2D, The Disc-To-Disc copy program started back in October 1987 as
a programming exercise.  At that time the new DOS 3.30 and PS/2 machines
with 1.44MB floppy disks became available.  But the DOS utility named
DISKCOPY could only copy these disks when exchanging source and
destination several times.  Exchanging source and destination disk was
rather dangerous.

So the idea was to use the so-called "extended memory" of the machine to
get more data into the RAM.  At these times the 6MHz IBM PC/AT with 1MB
RAM were available, and people wondered what to do with these 384kB of
additional RAM.  I can't remember whether I started using Microsoft C 4.0,
but definitely I started with Turbo-C 1.0 (which was rather buggy then).

I had decided not to mess with interrupts, nor did I have a specification
for XMS, so that I decided to use the extra RAM indirectly through
RAMDRIVE.  The first version of the program simple tried to write the extra
data on a so-called "overflow drive" which had to be a "fixed disk".
Even not on the wishlist, I prepared the program for multiple copies of one
disk, and I added a special algorithm to copy only as much tracks as really
needed.

I later revisions I added support for EMS and XMS memory access. Also I
added the ability to copy non-DOS disks.  As the program does not mess with
interrupts and hardware, the program can deal with almost any format the
running DOS can handle.  Unfortunately MS-DOS is unable to format the
higher density formats that are used for Windows applications and OS/2.

As I thought the program is good enough to share, I represented the original
program as "restricted freeware" and as "registered software".  Up to now
I have less than 5 registered users, and the money earned did not compensate
for the roughtly $10000 spent on computers.

For the 10th anniversary of D2D I had planned a special release named
`Sophia', but I rarely had time to work on it.  Nevertheless it's here:
The GPL version of D2D-2.32, including some of the recent enhancements of
D2D-3. (D2D-3.8 is still avaliable in its current state, including the
ability to use "disk images" on a hard disk instead of floppy disks).

This release was compiled with Borland C 3.1 under MS-DOS 5.0.

Ulrich Windl
<Ulrich.Windl@rz.uni-regensburg.de>
