text: #include <sys/types.h>
  #include <sys/param.h>
  #include <sys/socket.h>
  #include <netinet/in.h>
  #include "readwrite.h"
  #include "byte.h"
  #include "socket.h"
  
  int socket_connect4(int s,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 connect(s,(struct sockaddr *) &sa,sizeof sa);
  }
  
  int socket_connected(int s)
  {
    struct sockaddr_in sa;
    int dummy;
    char ch;
  
    dummy = sizeof sa;
    if (getpeername(s,(struct sockaddr *) &sa,&dummy) == -1) {
      read(s,&ch,1); /* sets errno */
      return 0;
    }
    return 1;
  }
  