How do i check my hard disk for errors?

[Bruno Wolff III]

On Sat, Feb 19, 2005 at 12:31:56 +0530,
  Rajev Mhasawade <rcmpost at gmail.com> wrote:
> I had to reinstall fedora bcoz i couldnt remove packages and
> essentially had to reformat /usr and /.
> And now i fear my HDD has produced errors.When Fedora boots it gives
> msgs like "/usr clean few numbers/few number blocks"
> When i right click to /usr folder i get this reading as well- 
> 103560 items, totalling 1.8 GB
> (some contents unreadable)
> 
> Is my HDD damaged.How do i cheack and correct it?Plz help :((
> rajev

Running the smartd daemon is a good idea1.

If you aren't using raid, you aren't going to be able to totally recover
from this if there are unreadable sectors on the disk.

You should probably start by backing up anything you care about on the
disk.

You can use badblocks to check out a disk. If you feel you have backed
up what you need, you can run write tests by running off a live CD.