mj@myrias.UUCP (Michal Jaegermann) (06/24/86)
[ munch, munch ... ]
I was hit by a rather obscure bug in TOS, Below is an exact description
of what happened. Does anybody else happen to stumble upon the same
problem?
--------
SYSTEM
Atari 1040 ST. TOS in ROM (of course). One DS drive.
Only operating system and basic accesories loaded. No RAM-drive
at the moment.
ACCESORIES (which you need to reproduce events)
A disk which sometimes in a past was initialized as two-sided.
Currently re-initialized as a single sided and completely filled
with files.
SITUATION
At the Desktop, by a mistake I tried to copy one more file to
the disk. Without RAM-drive I used "copy a: to b: and swap, swap,
swap..." method.
RESULTS
Operating system happily went throgh motions. No error reported
during the whole operation. First indication that something went
amiss was that a directory listing looked exactly as before the
operation. As it turned out some parts of a file which I tried
to copy - a program file - were deposited on the disk overwriting
an end of one file and a begin of the next one. Apparently some
pointers in FAT for the second file were changed making the last
sector of the second file its begin - at least in some circumstances.
HOW TO AVOID
I don't know. Be careful and tip-toe around.
-----
Michal Jaegeramnn
Myrias Research Corporation
Edmonton, Alberta, CANADA