似乎无法将客户的地址保存到sourceMsgs [j]

时间:2019-10-31 00:35:39

标签: c udp ip-address sendto sockaddr-in

标题说明了一切,这也许很简单,但是我在编程方面是新手,因此是个愚蠢的问题。

我有:

printf("sourcemsg: %s", inet_ntoa(sourceMsgs[j].sin_addr));

查看在sourceMsgs [j]中保存的IP地址是否正确,是否正确,所以我假设问题出在:

nbytes = sendto(s, response , reslen, 0 , (struct sockaddr *)&sourceMsgs[i],sizeof(sourceMsgs));
            //    (uk: save the coordinates/address of the source of the received message
            //    in table sourceMsgs at index nReceivedMessages).

            //I'm pretty sure what I did here is wrong

            int j = nReceivedMessages;
            sourceMsgs[j].sin_addr = cli_addr.sin_addr;
            printf("sourcemsg: %s", inet_ntoa(sourceMsgs[j].sin_addr));
            nReceivedMessages++;
            total += receivedValue;

            printf("<Servidor> Valor recebido: %f\n", receivedValue);
            //(uk: <Server> Received value)

            if(nReceivedMessages == 1){


                timeout = 1;
                setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(DWORD));

            }

        }

    }

    sprintf(response,  "Received Messages: %f Total: %f", nReceivedMessages, total);

    int reslen = sizeof(response);

    for(i=0; i<nReceivedMessages; i++){

        //    (uk: transmit the content of variable response, the previously defined string, to
        //    all the destinations in table sourceMsgs).

        nbytes = sendto(s, response , reslen, 0 , (struct sockaddr *)&sourceMsgs[i],sizeof(sourceMsgs));

如果该帖子非常不完整,我深表歉意,但这是我的第一篇。 谢谢您的提前帮助

修改:

似乎问题确实在于传递结构的长度(WSAError 10014)。 现在的代码是这样的:

nbytes = sendto(s, response , strlen(response), 0 , (struct sockaddr *)&sourceMsgs[i].sin_addr, sizeof(sourceMsgs[i].sin_addr));

我不太确定该怎么做,但是可能有另一种方法:

               sourceMsgs[j].sin_addr = cli_addr.sin_addr;
               printf("sourcemsg: %s", inet_ntoa(sourceMsgs[j].sin_addr));
               nReceivedMessages++;
               total += receivedValue;

因为我认为我的做法是一个但搞砸了。

2 个答案:

答案 0 :(得分:0)

sendto的参数应该是指向sockaddr结构的指针,而不是包含它的结构的指针。

nbytes = sendto(s, response , reslen, 0 , (struct sockaddr *)&sourceMsgs[i].sin_addr,sizeof(sourceMsgs[i].sin_addr));

答案 1 :(得分:0)

传递结构的长度可能有问题。

nbytes = sendto(s, response, reslen, 0, (struct sockaddr *)&sourceMsgs[i], sizeof(sourceMsgs[i]));

// sizeof(sourceMsgs) gives - ( sizeof(sourceMsgs[1] or struct sockaddr_in) * (No. of messages in array) ).

此外,我注意到使用setsockopt设置recv超时存在问题。有关说明,请参见SO_RCVTIMEO