| Title: | Atari ST, TT, & Falcon |
| Notice: | Please read note 1.0 and its replies before posting! |
| Moderator: | FUNYET::ANDERSON |
| Created: | Mon Apr 04 1988 |
| Last Modified: | Tue May 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 1433 |
| Total number of notes: | 10312 |
I'm writing some non-Gem software, in C. In one section of it I need to
copy a file from one disk to another. I have a few questions for
the ST gurus:-
1) How do I tell how many physical floppy drives there are on a system?
The call I've tried returns a bit vector indicating 2 drives, even
on a 1-drive system.
2) On a single drive ST, TOS can't/doesn't keep track of whether
disk A or B is currently in the drive - True?
3) The consequences of fumbling disks and having the wrong one loaded
at the wrong time during a single-drive copy - corrupt directory
and/or FAT?
4) Any hints on safeguarding against 3)? I remember reading about
a random number field written during formatting - can that be used
to identify disks?
(I need to make sure my software is fairly foolproof, I'm also the user).
Rgds, Brian
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 537.1 | I've been there | PRNSYS::LOMICKAJ | Jeff Lomicka | Wed Jul 19 1989 15:20 | 30 |
> 1) How do I tell how many physical floppy drives there are on a system?
> The call I've tried returns a bit vector indicating 2 drives, even
> on a 1-drive system.
peekw( 0x4A6) contains, according to the MWC manual, "Number of floppy
disk drives."
> 2) On a single drive ST, TOS can't/doesn't keep track of whether
> disk A or B is currently in the drive - True?
Only to the extent that it trusts you when you say you inserted disk A
or disk B. If TOS asks for disk B, and you re-insert A, then you loose.
> 3) The consequences of fumbling disks and having the wrong one loaded
> at the wrong time during a single-drive copy - corrupt directory
> and/or FAT?
It depends on the program. If you don't have any files open at the
time, it should be okay. If you do, then well...
> 4) Any hints on safeguarding against 3)? I remember reading about
> a random number field written during formatting - can that be used
> to identify disks?
You can Rwabs() block 0 and read the disk serial number out of the boot
block, but if you Rwabs() after a media change but before doing any
GEMODS I/O, you will totally screw up GEMDOS, as GEMDOS needs to know
when the media changes, and by doing an Rwabs(), you have circumvented
GEMDOS's way of finding out. Be sure to do some gemdos I/O (like
Fopen()) before doing the Rwabs(), and you will be okay.
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| 537.2 | Thanks... | MINDER::GILBERT | North UK Region Appl'n Centre @MCO | Fri Jul 21 1989 14:07 | 9 |
Thanks for your reply Jeff.
btw
I'd found system variable 0x4A6, but Abacus's ST Internals said
it only has values 0 or 2. It is wrong, your version is right.
The number of errors and omissions in that $%^& book is unacceptable!
rgds Brian
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| 537.3 | ? 2-disk games ? | NRMACU::BAILEY | Wed Oct 18 1989 10:35 | 7 | |
Does anyone out there know why so many games which require more
than one disk (e.g. Dungeon Master) can't use a second drive where
one is available. I get annoyed at having to continually swap disks
while there is a perfectly good drive sitting there doing nothing!
Chris.
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