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+
+Atari format support
+====================
+
+Both mkdosfs and dosfsck now can also handle the Atari variation of
+the MS-DOS filesystem format. The Atari format has some minor
+differences, some caused by the different machine architecture (m68k),
+some being "historic" (Atari didn't change some things that M$
+changed).
+
+Both tools automatically select Atari format if they run on an Atari.
+Additionally the -A switch toggles between Atari and MS-DOS format.
+I.e., on an Atari it selects plain DOS format, on any other machine it
+switches to Atari format.
+
+The differences are in detail:
+
+ - Atari TOS doesn't like cluster sizes != 2, so the usual solution
+   for bigger partitions was to increase the logical sector size. So
+   mkdosfs can handle sector sizes != 512 now, you can also manually
+   select it with the -S option. On filesystems larger than approx. 32
+   MB, the sector size is automatically increased (stead of the
+   cluster size) to make the filesystem fit. mkdosfs will always use 2
+   sectors per cluster (also with the floppy standard configurations),
+   except when directed otherwise on the command line.
+
+ - From the docs, all values between 0xfff8 and 0xffff in the FAT mark
+   an end-of-file. However, DOS usually uses 0xfff8 and Atari 0xffff.
+   This seems to be only an consmetic difference. At least TOS doesn't
+   complain about 0xffff EOF marks. Don't know what DOS thinks of
+   0xfff8 :-) Anyway, both tools use the EOF mark common to the
+   system (DOS/Atari).
+
+ - Something similar of the bad cluster marks: On Atari the FAT values
+   0xfff0 to 0xfff7 are used for this, under DOS only 0xfff7 (the
+   others can be normal cluster numbers, allowing 7 more clusters :-)
+   However, both systems usually mark with 0xfff7. Just dosfsck has to
+   interpret 0xfff0...0xfff7 differently.
+
+ - Some fields in the boot sector are interpreted differently. For
+   example, Atari has a disk serial number (used to aid disk change
+   detection) where DOS stores the system name; the 'hidden' field is
+   32 bit for DOS, but 16 bit for Atari, and there's no 'total_sect'
+   field; the 12/16 bit FAT decision is different: it's not based on
+   the number of clusters, but always FAT12 on floppies and FAT16 on
+   hard disks. mkdosfs nows about these differences and constructs the
+   boot sector accordingly.
+
+ - In dosfsck, the boot sector differences also have to known, to not
+   warn about things that are no error on Atari. In addition, most
+   Atari formatting tools fill the 'tracks' and 'heads' fields with 0
+   for hard disks, because they're meaningless on SCSI disks (Atari
+   has/had no IDE). Due to this, the check that they should be
+   non-zero is switched off.
+
+ - Under Atari TOS, some other characters are illegal in filenames:
+   '<', '>', '|', '"', and ':' are allowed, but all non-ASCII chars
+   (codes >= 128) are forbidden.
+
+- Roman <Roman.Hodek@informatik.uni-erlangen.de>