$ sudo badblocks -wsv /dev/sdb
Checking for bad blocks in read-write mode
From block 0 to 15425535
Testing with pattern 0xaa: done
Reading and comparing: 5645473 done, 36:56 elapsed. (0/0/0 errors)
5645480
5645482
5645487
done
Testing with pattern 0x55: ^C0.17% done, 43:47 elapsed. (0/0/4 errors)

Interrupted at block 31488