1 Sep
2004
1 Sep
'04
5:12 p.m.
On Wednesday 01 September 2004 22:30, der Mouse wrote:
Well, devices _are_ often special in various ways.
Most notably
here, disk devices normally do not support accesses that are not a
multiple of the sector size, aligned on sector boundaries. (Since
most emulators don't try to do anything else with disks, they
probably will work fine. This is partly just general misimpression
correcting, but also partly because you may run into trouble if you
try to use something like a CD - the CD blocksize is fundamentally
2352, which turns into 2K for a data CD (the other 304 bytes going
for ECC and suchlike), and many CD drives don't support sub-2K
accesses, meaning you may not be able to use a CD to back even a
read-only disk.)
A proper OS device driver will figure out that you're not
reading/writing a whole block (or on a block boundary), and give you
back or modify only what's required, when using a read()/write()
syscall or fread()/fwrite(). :)
Pat
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