Haiku trac ticket 2696 refers to some unimplemented functions:

http://dev.haiku-os.org/ticket/2696

The task is to research the missing functions and other potentially missing parts in Haiku and to report the results.  Be sure to read through the comments on the trac ticket.  This tasks isn't to solve them, just to identify which parts are still needed.  A later task might be added to implement some or all of them.