Check is socket is blocking (Winsock specific) [duplicate]

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Poss开发者_JS百科ible Duplicate:

In Win32, is there a way to test if a socket is non-blocking?

This is how I set socket to non-blocking mode in windows.

unsigned long mode = is_blocking ? 0 : 1;
int ret = ::ioctlsocket(m_Socket, FIONBIO, &mode);

In my complex library I'm getting occasional locks because some sockets passed to it weren't set to non-blocking mode. So, I would like to add and assert to be able to see where non-blocking socket is passed from. The problem is that I have no idea how to test if socket is blocking or not.

On unix, it's simple:

long arg = 0;
if((arg = fcntl(m_Socket, F_GETFL, NULL)) < 0) { 
   return ERROR;
}
bool was_blocking = (arg & O_NONBLOCK) != 0;

so, how can I test if socket is blocking on windows.

thanks

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Windows does not offer any way to query whether a socket is currently set to blocking or non-blocking.