Saturday, January 18, 2014

Why FAT Doesn't Belong In Your Flash Drives

I have been moving all my wife's applications over from her Windows XP desktop to a Windows 7 notebook.  One of the applications that she uses regularly is OpenLP, which is an open source presentation management system intended for church worship services.  We needed to export the song library that she has built over the years.  Some of them songs are not in the default library because they are new; some are there because they are songs that she has written.  OpenLP has an export facility, and it exported in XML format.  When I tried to copy all these XML files to a flash drive, it kept refusing to do so -- complaining that the file or directory name could not be created. 

Okay, I started to see a pattern: filenames with periods in them.  But some did not fit that pattern at all.  However, I was able to copy the files over the network from the desktop to the new notebook without trouble, and then import them into OpenLP.  Why?

I am guessing that it is because FAT32 (which is what the flash drive that I picked up off the coffee table used) has some filename limitation that is generally the case over our network.  I have not tried this on an NTFS flash drive, but I suspect that the problem would go away.

The more time that I spent with this Toshiba Portege R500, the more impressed I am with what a marvelous combination of size and speed it provides.  Compared to a tablet, it is just a little larger, and just a little heavier -- and for $100, it is hard to argue against it.


Josh said...

FAT32 has a number of limitations on number of files per directory, the naming structure of files, the length of the full filename, and some less obvious matters. The most relevant for your situation is that it has to create two file indexes for any file with a non-standard (8.3-compatible) name, and that doesn't always work right.

Root directories also have a limitation on the total number of files or directories, and while it's usually not a big issue, in extreme cases you can hit the cap with ~15 files.

NTFS doesn't have that issue, but NTFS isn't well-supported by older Mac or Linux systems, and it's not very efficient with space for drives under 10 GB.

Mauser said...

I have a little toy video recorder that takes SD cards, but requires FAT16 format. Good luck finding those now.