[O]

[..]
  1. OFFSETTYPE_MAX
  2. OFF_T_BITWIDTH
  3. OLDGNU_MAGIC
  4. OPT_FLUSH
  5. OPT_IGNORE_ERROR
  6. OP_COPY
  7. OP_DELETE
  8. OP_MOVE
  9. OS_SORT_CASE_SENSITIVE_DEFAULT
  10. OS_Setup
  11. OTHER_8BIT
  12. O_ALL
  13. O_BINARY
  14. O_LINEAR
  15. O_NONBLOCK
  16. OperationMode
[..]