node.js - Socket.io emit callback not firing on server side? -

my server emits events properly, emit callback never works. in following, nothing logged on console:

server:

io.sockets.emit('delete hint', {id: id}, function(data){                     console.log('callback');                 }); 

client:

socket.on('delete hint', function(data){     // display message before deleting     $('#' + data.id).fadeout(function(){          $(this).remove();     }); }); 

i've tried client side code function(data, fn) in case callback needed included on receiving function.

i'm using windows , command prompt shows following when socket.io emitting event:

websocket writing 5:::{"name":"delete hint", "args":[{"id":"1"}, null]} 

i can't figure out problem is, doing wrong?

a callback executed on sender computer when receiver computer calls

have @ code:

server:

io.sockets.on('connection', connectionfunc);  function connectionfunc (socket) {     socket.emit('delete hint', "data client", callthis); }  //this function executed when client calls function callthis (datafromclient){      console.log("call fired: " + datafromclient); } 

client:

    socket.on('delete hint', function(data, callback) {          console.log("i received: "+ data);         // call fire when u next line runs         callback("the callthis function on server run");                  }); 

you can opposite way.