socket_send6 - send a UDP datagram

       socket_send6  sends  len bytes starting at buf in a UDP datagram over the socket s to UDP port port on IP
       address ip.

       You can  call  socket_send6  without  calling  socket_bind6.   This  has  the  effect  as  first  calling
       socket_bind6 with IP address :: and port 0.

       The  meaning of scope_id is dependent on the implementation and IPv6 IP.  On link-local IPv6 addresses it
       specifies the outgoing interface index.  The name (e.g. "eth0")  for  a  given  interface  index  can  be
       queried with getifname.  scope_id should normally be set to 0.

         #include <libowfat/socket.h>

         int s;
         char ip[16];
         uint16 p;
         uint32 scope_id;

         s = socket_tcp4();
         socket_bind6(s,ip,p);
         socket_send6(s,"hello, world",12,ip,p,scope_id);

       socket_send6 - send a UDP datagram

       socket_send6  returns  0  if  the  datagram  was sent successfully.  If not, it returns -1 and sets errno
       appropriately.

socket_send4(3), socket_getifidx(3)

                                                                                                 socket_send6(3)

#include<libowfat/socket.h>

       ssize_t socket_send6(int s, const char* buf, size_t len,
                            const char ip[16], uint16 port, uint32 scope_id);