The bfs superblock

The following information is stored in the superblock:

• the magic number

• the size of the filesystem

  • the offset to the start of filesystem data (in bytes)

  • the offset to the end of filesystem data (in bytes)

• the sanity words

  There are four words used to improve the resilience during compaction. They are used by fsck(1M) to recover if there has been a system crash at any time during the process of compaction. See ``Compaction'' for more information.