ProDOS MLI internals

[maclagan@netcom.com (Ian Maclagan)]

I am trying to "force" ProDos to keep an accurate Volume Control BLock in 
memory when it has multiple files open. 
Background : I am wanting to modify Prodos so that several Apple IIs can 
share a common volume (on a Digicard network). The problem is that when 
the MLI needs to allocate a new disk block (when a file grows) ProDOS 
does not re-read the Volume Control Block off the disk, rather it uses 
the bitmap in memory to find the next free block. If two or more 
computers allocate a new block there is a good chance they will use the 
same block and this will corrupt the files or the volume if the block was 
being allocated to a directory file. Does anyone know how to convince 
Prodos to reread the free block information OFF THE DISK when it needs to 
allocate a new block to a file????
thanks, Ian Maclagan
My email address is - maclagan@netcom.com