user@debian:~$ sudo e2fsck -c /dev/sdc2
e2fsck 1.42 (29-Nov-2011)
Checking for bad blocks (read-only test): done
/dev/sdc2: Updating bad block inode.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Free blocks count wrong for group #10251 (32257, counted=32253).
Fix<y>? yes


/dev/sdc2: ***** FILE SYSTEM WAS MODIFIED *****
/dev/sdc2: 684413/176193536 files (0.4% non-contiguous), 50708231/352365568 blocks