io_getcookie - retrieve cookie

       io_getcookie  retrieves  a  cookie  (pointer  to  some  anonymous data structure you associated with this
       descriptor).

       Use io_setcookie(3) to associate a cookie with a descriptor.

       If you did not associate a cookie with this descriptor, io_getcookie returns NULL.

       The idea is that you put the state associated with a TCP connection you serve in a common  struct.   Then
       you  do not need to have your own data structure to retrieve the state for a connection, you can just use
       the data structure io_wait already maintains.  The lookup works in constant time and should not cause any
       cache misses.

       io_getcookie - retrieve cookie

io_wait(3), io_setcookie(3)

                                                                                                 io_getcookie(3)

#include<libowfat/io.h>

       void* io_getcookie(int64 fd);