recvfrom回复的数据包结构问题？

zhf69

对于这样一个recvfrom(recvfd, recvBuf, sizeof(recvBuf), 0, (struct sockaddr *)&recvaddr, &len)函数：
到底回复几个数据包，怎么会一个数据包存到recvBuf中，而recvaddr中有会有IP地址结构的一个信息呢？还有recvBuf中的IP头存的到底是什么东西？

rickxbx

one packet for one call, if you use raw socket(also called packet), you will get the whole packet stored in the recvBuf. if you create tcp/udp socket, then the recvBuf will get data which follows the tcp/udp header(so you cannot find the ip information in this buffer), recvaddr is useful here to tell you the ip information about the remote host