C语言怎么实现网页的数据交换？

#include
#include
#include

main(int argc,char *argv[]){
  char    buff[4096];
  SOCKET    sock;
  SOCKADDR_IN    addr;
  WSADATA    wsa;
  WORD    wVersionRequested;
  struct hostent    *hs;
  int    count, len;
char *url="www.sample.com";

if (argc!=4) {printf("Error!
"); return -1; }
len=(strlen(argv[1])+strlen(argv[2])+strlen(argv[3])+49);

  wVersionRequested = MAKEWORd( 2, 0 );
  if (WSAStartup(wVersionRequested , &wsa)!=0){
    printf("Winsock Initialization failed.
"); return -1;
  }

  if ((sock=socket(AF_INET,SOCK_STREAM,0))==INVALID_SOCKET){
    printf("Can not create socket.
"); return -1;
  }

  addr.sin_family    = AF_INET;
  addr.sin_port    = htons(80);
  _snprintf(buff, 4096, "POST /cgi-bin/forum.cgi HTTP/1.1
"
    "Host: %s
"
    "Content-Type:
application/x-www-form-urlencoded
"
    "Content-Length: %d
"
    "
"
    "action=add&Title=%s&URL=
http://%s&yuzi=1&Description=%s
",
    url,
    len,
    argv[1],
    argv[2],
    argv[3]);
  if ((addr.sin_addr.s_addr=inet_addr(url))==-1){
    if ((hs=gethostbyname(url))==NULL){
    printf("Can not resolve specified host.
"); return -1;
    }

    addr.sin_family = hs->h_addrtype;
    memcpy((void *)&addr.sin_addr.s_addr,hs->h_addr,hs->h_length);
  }

  if (connect(sock,(LPSOCKADDR)&addr,sizeof(addr))==SOCKET_ERROR){
    printf("Can not connect to specified host.
"); return -1;
  }

    send(sock,buff,strlen(buff),0);
    recv(sock,buff,sizeof(buff),0);
    closesocket(sock);
  }
  return 0;