Messages in this thread | | | Date | Mon, 5 Apr 2004 12:30:08 +0200 | From | Marco Roeland <> | Subject | Re: fat32 all upper-case filename problem |
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On Sunday April 4th 2004 James Vega wrote:
> I've run across an interesting problem with creating all upper-case > files/direcotries on fat32 partitions. After creating a file in all > upper-case, I can access it for a short time using either the all > upper-case name or the all lower-case name. After a short amount of time > (or a umount/mount), I can only access the file via the all lower-case > name. I'm currently using kernel 2.6.4, but I've been seeing this since at > least November of last year. > > Example:
You forgot a 'ls /usbdrive' *before* the 'touch'. Now we don't know whether it was empty before. We'll assume so.
> debil% touch /usbdrive/CASE > debil% ls /usbdrive > case
This suggests that you've mounted your usbdrive (vfat probably?) _specifically_ with the option to force lowercase filenames. The default is to preserve the case of the filename (to the filename *should* be CASE here) and to see both names as equals.
Another possibility is that there *was* already a file called 'case' and that the actual writing of the 'CASE' file in the directory is postponed until some sort of 'sync' operation. This also would need a specific 'case-sensitive' mount option.
> debil% ls /usbdrive/CASE > /usbdrive/CASE > debil% ls /usbdrive/case > /usbdrive/case
The above normally can only happen if there really are *two* files, one name 'case' and the other 'CASE'. So a case sensitive filesystem.
> debil% umount /usbdrive && mount /usbdrive > debil% ls /usbdrive/case > /usbdrive/case > debil% ls /usbdrive/CASE > ls: /usbdrive/CASE: No such file or directory
Looks like you have mounted the thing with case-sensitiviy *and* forcing lowercase filenames always. Either there is a bug in the combination, or perhaps there is a bug in that the uppercase name is cached for some time in VFS until the lowercase name is reread from the usbdrive?
When you test this please be very careful to reproduce every start and end condition *exactly*. <Bad pun alert> It's very easy to look at Heisenbugs here, with all these virtual filenames in case space. </Bad pun alert>
In practice I'd suggest using default mount options, except perhaps the 'uid=', 'gid=' and 'umask='. -- Marco Roeland - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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