Enums starting with `b' in xnu

• BTreeInformationVersio bsd/hfs/hfscommon/headers/BTreesInternal.h:183
• BTreeIterationOperation bsd/hfs/hfscommon/headers/BTreesInternal.h:191
• BTreeKeyLimit bsd/hfs/hfs_format.h:516
• BTreeType bsd/hfs/hfscommon/headers/BTreesInternal.h:208