where are fsck return values documented?

I see /etc/rc.d/fsck checks fsck return values.

Where are they documented?

I see some in fsck_* sources.

I think 4 is for fsck_msdos.

8 is in fsck_msdos and fsck_ffs and fsck_lfs

fsck_ext2fs, fsck_ffs and fsck_lfs have 12

I am not sure about 2.

And where does 130 come from?

  Jeremy C. Reed