iob_bytesleft - how many bytes are still to be sent?

       iob_bytesleft  returns the number of bytes that still need to be sent in this IO batch.  If you just want
       to see whether you need to call iob_send again, there  is  no  advantage  in  this  function  to  calling
       iob_send directly and looking whether it returned 0.

       iob_bytesleft - how many bytes are still to be sent?

iob_send(3)

                                                                                                iob_bytesleft(3)

#include<libowfat/iob.h>

       uint64 iob_bytesleft(const io_batch* b);