File Systems

I am returning to RPi after a long break caused by illness and am now using a Model B with the NOOBS RISCOS version (5.19). I find I can use various USB sticks that are to hand as supplementary storage besides the main SDcard using SDFS. and ShareFS links to me to my Risc PC perfectly well). Both ScsiFS and FAT32FS on these sticks seem to work. Can someone please explain the pros and cons of using the various systems.

I apologise if I have posted this inappropriately as a new topic – I can’t find anything suitable after much searching.

Do not use SCSIFS on pen drive larger than 2Gbytes. FAT32fs is (AIUI) slightly flakier than SDFS (which is well written). LANMan98 is better than sharefs for accessing external drives via the ethernet.

FAT32fs? I thought that could cope with larger drives.

Absolutely do not use standard DOSFS. I don’t know about today, but a year or so back it happily mounted a 4GiB device (which it couldn’t handle) and due to its inabilities, ended up trashing the filesystem badly enough that it crashed chkdsk on XP when trying to repair the damage.

If I mount anything large on the Pi, it is an SD card in a USB reader with write protect on. And DOSFS nowhere in sight.

Be aware that due to dumb patent issues, the long file names created do not have a valid short file name equivalent. This is by design (Linux does the same thing) as a work around the software patent on LFNs. On modern operating systems, this is not a big issue. But if you should happen to have a Win32 box around………

It should be possible to rename a file as a short name by giving it an 8.3 style name in capitals, though for me this seems to work most of the time, but not when I really want it to (such as when I have just copied RISCOS.IMG to the boot partition and have pressed Reset to boot it).

Sorry to cast aspersions, but I think that, in this case, Chris Hall’s advice is misleading.

DOSFS is the one not to attempt to use on pen drives etc. above 2 GB. SCSIFS is no problem, but is only going to work with FileCore-formatted drives.

FAT32FS ceased to be flaky many versions ago, in my experience.

Since any time (not sure 5.20?), I mean DOSFS can use devices above 4GB.

Aspersions were correctly cast, mea culpa. What I meant (I think) was don’t use SCSIFS on FAT formatted pen drives bigger than 2Gbytes UNLESS you have fat32fs as DOSFS (which is always there) can’t do it and doesn’t know that it can’t so will open them, see the root directory (only) but screw up if you use it.

(Incidentally I never said that fat32fs can’t cope with larger drives: it can.)