fopen returns NULL, even when the file exists

[AJJ]

Hi,
When the system (linux) undergoes an abrupt shutdown, on reboot few files stored in flash are getting corrupted. After reboot if I try to open those files using fopen, it returns a NULL pointer, so the code takes it as "File not found" case and creates a new file with default values (This overwrites the required data present in the corrupted file).

Do anybody have any idea on how to recover the data from the file even if it is corrupted...
As this occurs rarely I do not have the errno or the corrupted files with me.

Any suggestions or ideas on this would help me to proceed further in debugging this issue,

Thanks in advance...

[Rubberman]

Please show the code you are using to open the file. In any case, it is likely that since the system panic'd you need to recover the device with fsck since it is likely that the directory structure has become munged as well. BTW, what file system are you using on your flash drive, fat32, ntfs, or ext2. For Linux use, ext2 is preferable. FAT file systems are very fragile and recovering data from an ntfs volume is problematic at best.