Microsoft, TomTom Settle Patent Infringement Battle (eWeek) [LWN.net]

Microsoft, TomTom Settle Patent Infringement Battle (eWeek)

Posted Mar 31, 2009 15:37 UTC (Tue) by etienne_lorrain@yahoo.fr (guest, #38022)
Parent article: Microsoft, TomTom Settle Patent Infringement Battle (eWeek)

Just wanted to check if (what I think the patent contains without reading it) is implemented by Linux, so I did:

[root@fc10 ~]# mkdir /mnt/disk
[root@fc10 ~]# mount -t vfat /dev/fd0 /mnt/disk
[root@fc10 ~]# mkdir /mnt/disk/tmp
[root@fc10 ~]# echo "dummy file with long filename" > /mnt/disk/tmp/alongfilename.txt
[root@fc10 ~]# ls /mnt/disk/tmp
alongfilename.txt
[root@fc10 ~]# umount /mnt/disk
[root@fc10 ~]# mount -t msdos /dev/fd0 /mnt/disk
[root@fc10 ~]# ls /mnt/disk/tmp
alongf~1.txt
[root@fc10 ~]# umount /mnt/disk
[root@fc10 ~]# mount -t vfat /dev/fd0 /mnt/disk
[root@fc10 ~]# cat /mnt/disk/tmp/alongf~1.txt
dummy file with long filename
[root@fc10 ~]# cat /mnt/disk/tmp/alongfilename.txt
dummy file with long filename
[root@fc10 ~]# umount /mnt/disk
[root@fc10 ~]#

So obviously, there is two way to access a file with a long filename on Linux/VFAT: by its long filename (/mnt/disk/tmp/alongfilename.txt) and by its short filename (/mnt/disk/tmp/alongf~1.txt).
It seems that I would not miss the access by its short filename...

Etienne.

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LFN fix for Linux

Posted Apr 3, 2009 21:48 UTC (Fri) by spitzak (guest, #4593) [Link]

Here's an idea:

Apparently it is ok to *read* LFN FAT disks. But not to create files with such names.

How about Linux change the FAT driver so when you try to create a non-existent file needing a long name, it writes the name is a whole new way (perhaps in a hidden file). This will avoid the patents. It will read both the new and old ways of doing LFN. Recommended that the implementation be given in BSD code so that everybody who wants to can implement it.

Any FAT disk will look fine in the Linux device. But when you plug it back into Windows they will see MICROS~ style filenames for all the new files and it will look crappy. They put it back on the Linux machine and it looks fine! Suddenly it is Windows that looks like the broken system.

LFN fix for Linux

Posted Apr 4, 2009 0:31 UTC (Sat) by giraffedata (subscriber, #1954) [Link]

Any FAT disk will look fine in the Linux device. But when you plug it back into Windows they will see MICROS~ style filenames for all the new files and it will look crappy. They put it back on the Linux machine and it looks fine! Suddenly it is Windows that looks like the broken system.

Nah, it'll look like the Linux device is broken. Files you generate with every device except the TomTom look fine in Windows, but the TomTom's files look crappy. Must be TomTom that's broken -- it doesn't know how to export files. And it must be because it uses that second-rate Linux thing.