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The receiver creates the pipe when it creates and binds its socket.  It >> creates only one pipe instance.  The sender connects to the pipe, writes, and >> closes its handle.  But the pipe is not available for another sender to >> connect to until the receiver reads the message, after which it disconnects >> the sender. >> > > This > >   https://docs.microsoft.com/en-us/windows/win32/ipc/named-pipe-instances > > seems to indicate that multiple pipe instances are needed to handle multiple > clients nicely - it also has sample code for such. Yes, we do that for stream sockets that are listening. Whenever there's a connection, a new pipe instance is created so that the listening socket can continue listening. But I don't see an easy way to adapt this to datagram sockets, and I'm not even sure it's appropriate in that case. Ken