int recv_buffer(int fd, char *buf, size_t size);
int para_accept(int fd, fd_set *rfds, void *addr, socklen_t size, int *new_fd);
int recv_buffer(int fd, char *buf, size_t size);
int para_accept(int fd, fd_set *rfds, void *addr, socklen_t size, int *new_fd);