Please backup your SD card!

A couple of users have reported a corrupt file system on their SD cards after using DSmaps. I’ve been using the unreleased 0.1a version of DSmaps for a few weeks now, during which time I’ve accumulated over 3,000 files in my tile cache without experiencing anything like that. In fact I haven’t had as much as a hang. And judging by various download logs, hundreds of you have being trying out DSmaps today without any problems at all. So while these seem to be rare occurrences, please remember that this is alpha software and these things are an unfortunate fact of life when using any pre-release software – particularly alpha versions. The bottom line is that you should back up the contents of your SD card before you try out DSmaps or any pre-release software.

As to finding a resolution for the problem…the only file system writes done by DSmaps are creating directories to act as cache buckets, and creating the cache files themselves. Nothing is ever renamed, moved or deleted. Everything is done using the standard C library functions. Exotic, barely-documented functions are not used, nor is there any direct access to the raw file system. So it’s difficult to know what could be causing this. But one theory I’m working on is that the problem relates to the type of file system on your SD card. In all my development and testing I’ve been using FAT16, which was the default on my SD card. But at least one of the affected users was using FAT32 (possibly the others too – they haven’t said). I’ve reformated my SD in an effort to repro this, and I’m also doing a bit of research into potential issues with libfat on FAT32.

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