Write error reporting
---------------------
Due to the buffer cache, write errors cannot always be reported to
the writing user program as soon as the write system call returns.
Indeed, the actual writing may take place much later. If a write error
is encountered, the floppy driver stores information about it in its per
drive write error structure. This write error structure stays until
explicitly cleared. It can for example be queried by a backup program
which wants to make sure that the data has been written successfully.
`--clrwerror'
Clears the write error structure.
`--printwerror'
Prints the contents of the write error structure:
`write_errors'
is a count of how many write errors have occurred since the
structure was last cleared.
`badness'
is the maximal number of retries that were needed to complete
an operation (reads, writes and formats).
`first_error_sector'
is where the first (chronologically) write error occurred.
`first_error_generation'
is the disk change generation in which did the first write
error occurred. The disk change generation is a number which
is incremented at each disk change.
`last_error_sector'
and
`last_error_generation'
are similar.