筆者遇到下位機發過來的幾百k的文件,爲了調試方便,一開始並沒有加協議
後面發現在OnRecv的回調中打印消息時,居然UDP丟包了
後面經過多次分析,才發現windows默認的socket緩衝區是8k
使用setsockopt改大後就不會丟包了
int nRecvBuf = 700 * 1024;//設置爲700K
if (0 != setsockopt(m_sock, SOL_SOCKET, SO_RCVBUF, (const char*)&nRecvBuf, sizeof(int)))
{
TRACE(_T("setsockopt buf size failed.\n"), WSAGetLastError());
return FALSE;
}
if (getsockopt(m_pListenContext->m_Socket, SOL_SOCKET, SO_SNDBUF, (char*)&optVal, &optLen) != SOCKET_ERROR) pirnt("SockOpt Sendbuff Value: %d\n", optVal);
if (getsockopt(m_pListenContext->m_Socket, SOL_SOCKET, SO_RCVBUF, (char*)&optVal, &optLen) != SOCKET_ERROR) pirnt("SockOpt Recvbuff Value: %d\n", optVal);