hard drive sector testing on Ubuntu

[lazer100]

further to an earlier topic,

I would like to do a sector test of a hard drive on Ubuntu,

this is a read and write test of sectors.

is there any software to do this on Ubuntu 8.10?


this is where the software would say read each sector,
make some arbitrary change to the data, ideally change
every byte,

write that,

then reread the sector and see if the data is correct,

and then perhaps restore the original data.


For speed with an unformatted disk, one could say 
write data which is the timestamp repeated, 

eg 20120928230510 repeated up to 512 bytes.

2012092823051020120928230510....

then reread that sector and see if its the same data,

looking also for error messages for the read and the write.



but if the test preserves the data that would also be alright,
it would just take longer.

I have a problem drive, and I need to determine the problem sectors
in order to return the drive to the manufacturer. They said to
use the Windows sector testing, but that reported no error. However
both on Windows and Linux, software has reported read and write errors.

so I dont trust the Windows sector testing and would like to verify
by some other means before I believe that!




Further on this topic, is there any way to read and write to a specific
sector number on say /dev/sdc or /dev/sdc1

I can read and write sequentially with dd eg

dd if=/path/file of=/dev/sdc1

would write the file sequentially, 

does Linux have a trick for accessing a particular sector number,
and will the sector numbers of each volume begin at say 0, eg

0,1,2,... 

?



sequentially accessing the drive is less satisfactory for 
testing a 1tb volume as I would have to synthesize a 1tb file,
and that wouldnt test the control sectors

I guess I could subdivide the drive into 8 unformatted logical drives of 128G,

and then write a 128G file to each, then filecompare that file with each,

but is there a less severe way of testing sectors, where every sector is
tested?