WSARecvFrom blocking

本文关键字：blocking WSARecvFrom 更新时间：2023-10-16

由于某种原因，当我调用WSARecvFrom函数时，直到收到一些东西才返回。

_socket = WSASocket(AF_INET, SOCK_DGRAM, IPPROTO_UDP, NULL, NULL, WS_OVERLAPPED);
...
sockaddr_in addr = ...
if(bind(_socket, (const sockaddr*)&addr, sizeof(addr)) != EXIT_SUCCESS) { ... }
...
HANDLE _handle = CreateIoCompletionPort((HANDLE)_socket, _ioHandle, NULL, NULL);
...
_recvOverlap->OVERLAP.hEvent = WSACreateEvent();
DWORD sz = 0, flag = 0;
return WSARecvFrom(_socket, _recvBuf, 1, &sz, &flag, (sockaddr*)_recvAddr, &_recvAddrSz, (LPWSAOVERLAPPED)_recvOverlap, NULL);

将WS_OVERLAPPED(值为0)改为WSA_FLAG_OVERLAPPED(值为1)。您没有正确创建重叠套接字，因此_recvOverlap被WSARecvFrom()忽略。