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RE: VFAT.XFS versus MagiC



> Adding VFAT-compatibility to the TOS fs should be quite easy, VFAT is
> identical to FAT except for the extra entries in the FAT-table (For
> the long filenames).

Actually the difference is that the directory info is changed by adding
"illegal" directory entries with the extended (long) filename encoded
in Unicode. You have to be careful when decoding the directory info
since TOS/DOS might have destroyed the extra directory entries mistaking
them for free/illegal entries... This means that you have to read and
interpret the directory entries yourself (by raw sector reads) but you
can load (and append write into etc) files with long file names with normal
TOS calls since all such files also have a unique DOS/TOS name. However
VFAT can be used onto of FAT32 which cannot be read by TOS and in that
case you will have to do your own filehandling routines yourself too..
(BTW reading the directory information for subdirectories also means
 interpreting the FAT since the subdirs are stored like a file using
 a cluster chain (linked by the FAT). The FAT is nothing more than
 vector containing cluster numbers which is used as next pointers
 in a single linked list of clusters making up a file. A cluster is
 the smallest allocatable quota of sectors on a floppy this is usually
 2 sectors ie 1024 bytes.)  
 
Regards
 Sven