Reading Hard Drive Blocks

[Richard Foulk]

} I was wondering if there is some way to go out and actually read the block
} before I delete it, so I can see what it is and prepare for its removal.
} Actually, what I was really thinking of doing was renaming whatever file
} it happened to be in to file.old and copy it to itself.

If you do find the file, perhaps by noticing that when you cat it to
/dev/null that you get another error reported in your log file, you
should be able to mv it to another name (same filesystem).  Then it
would be best restore the file from your backups.

} Another thing I was wondering is what causes soft errors.  I mean, how
} does the computer recover from something like a bad hard disk read?

Either the disk controller catches the error and corrects it through
various means, or the driver does some retries until it succeeds
without an error report from the controller.

Richard