socket_send.c

It support IPv4 and IPv6 unicast and multicast and contains a trivial sender and a trivial receiver

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include "byte.h"
#include "socket.h"

int socket_send4(int s,const char *buf,unsigned int len,const char ip[4],uint16 port)
{
  struct sockaddr_in sa;

  byte_zero(&sa,sizeof sa);
  sa.sin_family = AF_INET;
  uint16_pack_big((char *) &sa.sin_port,port);
  byte_copy((char *) &sa.sin_addr,4,ip);

  return sendto(s,buf,len,0,(struct sockaddr *) &sa,sizeof sa);
}