怎么用WSAGetLastError ？

[聆心雨落]

我做的程序，调试没有问题，但就是不执行结果，怎么解决啊？我做的是屏幕截图，就是出现不了屏幕图像。
我看到好多说 用 WSAGetLastError 检测的，怎么用的，怎么才能知道错误呢？谢谢了

[WaistCoat19]

WSAGetLastError是获取Socket错误的。

如果普通API函数调用失败后应该调用GetLastError。

[聆心雨落]

我就是想获取socket错误，可是我不知道怎么用？

[ouyh12345]

if( 0 > send(...))
{
printf("send error:%d\n", WSAGetLastError);
//错误处理
}

[聆心雨落]

把这句话放在哪里呢？

还有调试的时候没有问题，但就是不执行可能是什么原因呢？我现在做的是屏幕抓图，涉及到套接字，不知道是不是套接字的问题。

[WaistCoat19]

判断函数返回值，如果失败了离开调用WSAGetLastError

[一条晚起的虫]

但就是不执行可能是什么原因呢
//如果是多线程的，可能涉及线程同步问题。

在socket函数失败之后，调用WSAGetLastError判断具体错误

[聆心雨落]

//在socket函数失败之后，调用WSAGetLastError判断具体错误//

应该怎么调用呢？

我发现我真的什么都不会，谢谢大家的帮助了，我真的很想努力的解决问题

[写不动代码的人]

先学会知道socket是否失败

[一条晚起的虫]

if(socket失败)
{
DWORD dwError = WSAGetLastError();
}

[一条晚起的虫]

http://msdn.microsoft.com/en-us/library/ms741580(VS.85).aspx

最好的函数手册 MSDN
在线的 msdn.microsoft.com/en-us

[flyuniverse_shell]

switch (WSAGetLastError())
	{
	case WSANOTINITIALISED:
		TRACE("A successful WSAStartup call must occur before using this function. ");
		break;
	case WSAENETDOWN:
		TRACE("The network subsystem has failed. ");
		break;
	case WSAEACCES:
		TRACE("The requested address is a broadcast address, but the appropriate flag was not set. Call setsockopt with the SO_BROADCAST parameter to allow the use of the broadcast address. ");
		break;
	case WSAEINVAL:
		TRACE("An unknown flag was specified, or MSG_OOB was specified for a socket with SO_OOBINLINE enabled. ");
		break;
	case WSAEINTR:
		TRACE("A blocking Windows Sockets 1.1 call was canceled through WSACancelBlockingCall. ");
		break;
	case WSAEINPROGRESS:
		TRACE("A blocking Windows Sockets 1.1 call is in progress, or the service provider is still processing a callback function. ");
		break;
	case WSAEFAULT:
		TRACE("The buf or to parameters are not part of the user address space, or the tolen parameter is too small. ");
		break;
	case WSAENETRESET:
		TRACE("The connection has been broken due to keep-alive activity detecting a failure while the operation was in progress. ");
		break;
	case WSAENOBUFS:
		TRACE("No buffer space is available. ");
		break;
	case WSAENOTCONN:
		TRACE("The socket is not connected (connection-oriented sockets only). ");
		break;
	case WSAENOTSOCK:
		TRACE("The descriptor is not a socket. ");
		break;
	case WSAEOPNOTSUPP:
		TRACE("MSG_OOB was specified, but the socket is not stream-style such as type SOCK_STREAM, OOB data is not supported in the communication domain associated with this socket, or the socket is unidirectional and supports only receive operations. ");
		break;
	case WSAESHUTDOWN:
		TRACE("The socket has been shut down; it is not possible to sendto on a socket after shutdown has been invoked with how set to SD_SEND or SD_BOTH. ");
		break;
	case WSAEWOULDBLOCK:
		TRACE("The socket is marked as nonblocking and the requested operation would block. ");
		break;
	case WSAEMSGSIZE:
		TRACE("The socket is message oriented, and the message is larger than the maximum supported by the underlying transport. ");
		break;
	case WSAEHOSTUNREACH:
		TRACE("The remote host cannot be reached from this host at this time. ");
		break;
	case WSAECONNABORTED:
		TRACE("The virtual circuit was terminated due to a time-out or other failure. The application should close the socket as it is no longer usable. ");
		break;
	case WSAECONNRESET:
		TRACE("The virtual circuit was reset by the remote side executing a hard or abortive close. For UPD sockets, the remote host was unable to deliver a previously sent UDP datagram and responded with a \"Port Unreachable\" ICMP packet. The application should close the socket as it is no longer usable. ");
		break;
	case WSAEADDRNOTAVAIL:
		TRACE("The remote address is not a valid address, for example, ADDR_ANY. ");
		break;
	case WSAEAFNOSUPPORT:
		TRACE("Addresses in the specified family cannot be used with this socket. ");
		break;
	case WSAEDESTADDRREQ:
		TRACE("A destination address is required. ");
		break;
	case WSAENETUNREACH:
		TRACE("The network cannot be reached from this host at this time. ");
		break;
	case WSAETIMEDOUT:
		TRACE("The connection has been dropped, because of a network failure or because the system on the other end went down without notice. ");
		break;
	default:
		TRACE("Unknown socket error. ");
		break;

[狂妄Beyond]

必须在加载winsock后，该函数才起作用

[麻浦区保安]

o 哦哦懂了！！