node.js giving Error: bind EINVAL

Question

I am learning Node.js and i am doing some sample code on udp .I am trying to implement a udp server to listen to multicast message and my basic code is this

var server = require('dgram').createSocket('udp4');
server.on('message', function(message, rinfo) {
console.log('server got message: ' + message + ' from ' + rinfo.address +
':' + rinfo.port);
});
server.bind(4000);
server.addMembership('230.1.2.3');

but node gives me an error,

events.js:72     
        throw er; // Unhandled 'error' event                     
        Error: bind EINVAL                      
at errnoException (dgram.js:440:11)     
at dgram.js:207:28                                   
at dns.js:72:18                                  
at process._tickCallback (node.js:415:13)            
at Function.Module.runMain (module.js:499:11)        
at startup (node.js:119:16)                          
at node.js:901:3   

also i am using windows 7 .please help...

Answer 1

Try

var server = require('dgram').createSocket('udp4');
server.on('message', function(message, rinfo) {
    console.log('server got message: ' + message + ' from ' + rinfo.address +
    ':' + rinfo.port);
});
server.bind(4000,function(){
    server.addMembership('230.1.2.3');
});

On second thought this error may arise due to several reasons like socket is busy, socket is closed, port is in use by some other process etc. so check for those too.

Found a reference after some googleing:https://github.com/joyent/node/issues/4944