The fsck -o p command (p is for preen) checks UFS file systems and automatically fixes the problems that normally result from an unexpected system shutdown. This command exits immediately if it encounters a problem that requires operator intervention. This command also permits parallel checking of file systems.
You can run the fsck -o p command to preen the file systems after an unclean shutdown. In this mode, the fsck command does not look at the clean flag and does a full check. These actions are a subset of the actions that the fsck command takes when it runs interactively.