I have a fat32 partition on linux that is used as an image for a virtual machine running an rtos. Linux needs to be able to mount and update files on this partition. The problem is there is some kind of fs compatibility issue with the linux and rtos fat32 implementations when the fs is fragmented by linux modifying files. Is there any linux utility (preferably open-source) for defraging fat32 filesystems? My current work-around is ridiculous: staging files on an ext3 partition and moving them to the vfat partition after completion, so I'm looking for a more elegant solution but I haven't found any such tool; google search returns forums where the solution is to just not use fat32, but that is not possible with what I'm doing. Thanks

Not unless something has changed recently. There are no true defraggers that I've found, and I searched extensively for one. There are however some filesystem-agnostic scripts that basically automate what you're already doing; moving files off of and back on to the drive, effectively defragging them.

One of them is available here: http://ck.kolivas.org/apps/defrag/

Thank you for the info -- you've saved me another day of searching! Defragging wouldn't matter if I could just definitively prove that Linux was doing correctly and the RTOS' implementation was bad, then I could submit a request for WindRiver to fix it. I highly doubt Linux is at fault here as I've never had a problem using vfat disks back and forth from Windows. Either way, that's a whole lot of time that I don't have.

I'll try to incorporate the script you linked to. The comment at the top of the script doesn't exactly give me a warm-fuzzy:

Wow! :-)