exFAT-aos3 53.4

exFAT filesystem for classic 68k Amigas

Short:        exFAT filesystem for classic 68k Amigas
Author:       Andrew Nayenko, Fredrik Wikstrom (68k port: Tobias Karlsson)
Uploader:     tobias karlsson piratkopia se (Tobias Karlsson)
Type:         disk/misc
Version:      53.4
Requires:     68020+; filesysbox.library 54+ (68k build included)
Architecture: m68k-amigaos >= 3.0

================================================================
  exFATFileSystem - read and write exFAT media on 68k AmigaOS
================================================================


WHAT IT IS

  A 68k build of Fredrik Wikstrom's exFATFileSystem, which upstream
  has only ever released for AmigaOS 4 (PPC) and AROS (i386) - as
  far as I can tell the only exFAT filesystem for classic 68k
  AmigaOS. CrossDOS reads FAT12/16/32 but not exFAT, and Poseidon
  is a USB stack, not a filesystem - it hands you the block device
  and stops there. Most sticks and cards over 32 GB come formatted
  exFAT from the factory; this handler mounts them: insert a stick,
  the icon appears on Workbench, and every program uses it as an
  ordinary volume.


FEATURES

  - No disk geometry to edit: the handler inspects sector 0 itself
    on every insertion, the way fat95 does. An exFAT boot sector
    there means superfloppy - used as-is. An MBR (primaries plus
    one level of extended) or GPT partition table is scanned and
    the first exFAT partition selected - judged by content, never
    by partition type bytes. Factory-formatted, superfloppy and
    hand-partitioned sticks all swap under the same EXFAT: device.

  - Files over 4 GB: 64-bit device offsets through the NSD 64-bit
    trackdisk extensions. A 4.5 GiB file was copied exFAT-to-exFAT
    and exFAT -> SFS\2 -> exFAT on the Amiga, SHA256-identical
    afterwards. (The 32-bit Examine API displays such sizes
    wrongly - the data itself is fine.)

  - Fast: 22 MB/s sustained sequential reads on an A1200 with a
    PiStorm32. Use 128 KB or larger buffers - smaller requests
    route through the per-sector block cache and are much slower.

  - DiskWatch: a small background command that makes the volume
    icon appear on insertion for Poseidon-hosted media, sleeping
    on Poseidon's binding events - zero calls while idle.

  - 68020 and 68060 builds included; filesysbox.library 54.9 (68k)
    and FbxDismount included.


INSTALLATION

  exFATFileSystem into L:, filesysbox.library into LIBS:,
  FbxDismount and DiskWatch into C:, the EXFAT DOSDriver (+ icon)
  into DEVS:DOSDrivers, and

    Run >NIL: C:DiskWatch EXFAT:

  in S:User-Startup. The supplied mount files assume Poseidon's
  usbscsi.device unit 0; point Device/Unit at something else if
  your media lives elsewhere. Full details, known behaviour and
  tuning notes are in the included ReadMe.txt.


STATUS

  Tested on an A1200 + PiStorm32-lite (Emu68, AmigaOS 3.2.3,
  Poseidon 6.0) with a 128 GB USB stick formatted three ways -
  superfloppy, MBR and GPT: mount, read, write, mkdir, delete,
  eject/reinsert all working, and the media verified clean
  afterwards with fsck.exfat on Linux. Run "FbxDismount EXFAT:"
  before pulling a stick, or it stays marked volume-dirty.


SOURCE

  https://github.com/creep-ltx/exfat-aos3

  The release archive there additionally carries a traced debug
  build (with Sashimi and a capture HOWTO) and the source changes
  of the 68k port.

  Upstream: github.com/salass00/exfat (GPL-2.0) and
  github.com/salass00/filesysbox (APL). The filesystem itself is
  Andrew Nayenko's and Fredrik Wikstrom's work; the 68k port, the
  partition auto-detection and DiskWatch are additions.


HISTORY

  53.4  First 68k AmigaOS release (upstream releases were OS4 and
        AROS only), plus partition auto-detection in whole-device
        mode and DiskWatch.