Creates an ONC RPC client handle for a buffered I/O UDP
    connection.
    Format
      #include  <rpc/rpc.h>
      CLIENT  *clntudp_bufcreate(struct sockaddr_in *addr, u_long
              prognum, u_long versnum, struct timeval wait, register
              int *sockp, u_int sendsize, u_int recvsize);