socket_mcloop4 - set multicast loopback

       socket_mcloop4  activates  multicast  loopback  for  the socket s if loop is non-zero, and deactivates it
       otherwise.  If loopback is activated, packets sent on this socket will be received on the same host.

       If something goes wrong, socket_mcloop4 returns -1, setting errno appropriately.

       socket_mcloop4 - set multicast loopback

socket_mcloop6(3), socket_mcjoin4(3), socket_mcleave4(3)

                                                                                               socket_mcloop4(3)

#include<libowfat/socket.h>

       int socket_mcloop4(int s,char loop);