Can chkfsys be used in QNX6 nor flash file system?

We use QNX 6.2.1 with nor flash file system in our embeded applications. There’s possibility that system power down without shutdown command, so flash filesystem crush sometimes, with error information “Crupted file system” when access.
I have tried “chkfsys” to solve the problem, but QNX always shows “There are no QNX4 filesystems mounted at this point”, and no checking actions, even I use -u or -P parameter.
Configurations related to filesystem in my build file shows below:
devf-sandpoint -s 0x70000000,16M -v &
flashctl -p/dev/fs0p0 -n/flash -l 7M -m
waitfor /flash
I have tried “chkfsys /flash” or “chkfsys -m /dev/fs0p0”, but none of them works.
So, whether “chkfsys” can be used in QNX6 nor flash file system? If not, is there another way to solve the filesystem cruption?

chkfsys is for QNX4 file system only. Flash have totaly different filesystem tune for flash caracteristic. I’ve heard 6.3 has much much better flash file system. Still I’m surprise you are seing such behavior. Even the 6.2.1 ffs was pretty good.

The filesystem protects this directory at runtime; in particular it can’t be removed or renamed, nor can it exceed 4096 bytes (128 entries). This can be used to skip an intensive filesystem-check the next time it starts.

117-101 practice test | 70-272 practice test | NS0-153 practice test

Flash programming takes time. It is a bit naiive to think that you can just power off a system while it is writing to flash and expect to never have a corruption. The file system of course tries to prevent corruption, but software cannot fix everything.

Even worse, I have seen systems that constantly write data to flash although most of the data isn’t really needed and could as well be written to a RAM disk. That the flash filesystem gives you a view over files that looks like a hard disk, doesn’t mean it is one.

In your case I would recommend a move to a later QNX OS version, like 6.4.1 or at least 6.3.2. If this is “absolutely impossible” because you find out (not believe, but find out) a migration would take more than a few weeks, then try the 6.2.1 “Supplemental Release”. AFAIR it contained an updated version of the Flash Filesystem with some windows of corruption possibility made a little smaller.