That almost sounds like libblkid isn't recognizing the FS. Can you try
running blkid on the device? If it can't detect the FS type, that might
be a place where there is an issue. The libblkid code is not based on
the drivers in the kernel, but is still essential for a portion of the
auto-detection of file systems in user-space.
Hi Brad
Indeed blkid does not recognize the FS type, thanks for the hint !
sudo blkid -p /dev/mmcblk0p1
/dev/mmcblk0p1: PART_ENTRY_SCHEME="atari" PART_ENTRY_TYPE="BGM"
PART_ENTRY_NUMBER="1" PART_ENTRY_OFFSET="2" PART_ENTRY_SIZE="131072"
PART_ENTRY_DISK="179:256"
I suppose this is because the Atari GEMDOS FAT16 partitions have a
variable sector size wich is larger that 512 bytes for partitions >
16MB, whereas MSDOS FAT16 always uses a 512 bytes sectorsize .
The disktype tool, provided in the archive, gave me the hint about the
sector size difference:
http://disktype.sourceforge.net/doc/ch03s03.html
and this technical guide, which has all the FAT subtilities explained:
http://info-coach.fr/atari/documents/_mydoc/Atari_HD_File_Sytem_Reference_Guide.pdf
sudo disktype /dev/mmcblk0p1
--- /dev/mmcblk0p1
Block device, size 64 MiB (67108864 bytes)
FAT16 file system (hints score 3 of 5, ATARI ST bootable)
Unusual sector size 4096 bytes
Volume size 63.95 MiB (67051520 bytes, 8185 clusters of 8 KiB)