#if LWIP_UDPLITE
/* used for UDP_LITE only */
u16_t chksum_len_rx, chksum_len_tx;
#endif /* LWIP_UDPLITE */
/* receive callback function
* addr and port are in same byte order as in the pcb
* The callback is responsible for freeing the pbuf
* if it's not used any more.
*
* ATTENTION: Be aware that 'addr' points into the pbuf 'p' so freeing this pbuf
* makes 'addr' invalid, too.
*
* @param arg user supplied argument (udp_pcb.recv_arg)
* @param pcb the udp_pcb which received data
* @param p the packet buffer that was received
* @param addr the remote IP address from which the packet was received
* @param port the remote port from which the packet was received
*/
void (* recv)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
struct ip_addr *addr, u16_t port);
/* user-supplied argument for the recv callback */
void *recv_arg;
};
不知道怎么向这个结构体指针传参数?
并且一般FTP传文件都要知道对方IP以及“用户名,密码”,可以这个发消息的结构体中没有涉及到“用户名,密码”方面。
谁有这方面的开发经验,请赐教,谢谢!