Re: usb flashkey disk copy error

John-Mark Gurne wrote this message on Sun, Sep 07, 2003 at 08:45 +0200:
raoul.megelas wrote:

> I have a copy error between hdd and a flashkey 1gig usb (easydisk)
> on Current dated August 28. Here is in short:
> 
> mount -t msdos /dev/da2s1 /flashkey
> cp myfile /flashkey/
> diff myfile /flashkey/myfile
> 	(ok).

> could you try a fsync /flashkey/myfile before the umount?

> umount /flashkey
> 
> mount (flashkey)
> diff myfile /flashkey/myfile
> 	(Binary file differ)!
> 
> It is not a flashkey disk error, it works on XP.
> Note that this error occurs on FreeBSD 4.8 too.
> 
> Please, can you tell me how to deal with that?
> And in an other hand can you tell me how to obtain the exact map of the flashkey
> to verify the writing on the disk.
> Thanks in advance for this newbie question.

> You're the second person that has reported corruption with USB umass
> devices.  I am interested in tracking down this problem, but it's a
> bit difficult since I haven't seen it myself.

> (I currently don't quite have a test bed box to play with, but I will
> in the next week.)
>  John-Mark Gurney				Voice: +1 415 225 5579

>     "All that I will do, has been done, All that I have, has not."

You have found the trick, fsync after cp works fine.
Thanks very much.

But why the fsync is not automatically done by umount on umass?

(note) if you need to test against flashkey i can do that if you want.)

	raoul
	raoul.megelas_at_libertysurf.fr