Experimental Physics and
Industrial Control System

The currently observed behaviour may be caused by an ARP lookup https://stackoverflow.com/questions/4165174/when-does-a-udp-sendto-block

Windows doesn’t look to provide MSG_DONTWAIT, you would probably need to set the socket into non-blocking mode with ioctlsocket() to get the equivalent behaviour, but that may cause undesirable consequences elsewhere (not looked);  however temporarily disabling/enabling blocking mode just around the call may be possible.

Freddie

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