int connectTCP(char *host, char *service,  int  nonblock);
 int connectsock(char *host, char *service, char *protocol,
                        int  nonblock);
 int connectUDP(char *host, char *service,  int  nonblock);
 int passivesock(char *service, char *protocol, int qlen);
 int passiveTCP(char *service, int qlen);
 int passiveUDP(char *service);