disable ipv6 for peer-to-peer discovery since it causes issues

Author: schollz

src/croc/croc.go

@@ -367,7 +367,9 @@ func (c *Client) Send(options TransferOptions) (err error) {
 		// add two things to the error channel
 		errchan = make(chan error, 2)
 		c.setupLocalRelay()
-		go c.broadcastOnLocalNetwork(true)
+		// broadcast on ipv6
+		//go c.broadcastOnLocalNetwork(true)
+		// broadcast on ipv4
 		go c.broadcastOnLocalNetwork(false)
 		go c.transferOverLocalRelay(options, errchan)
 	}