IE6 handshake error

[Deisss]

I'm getting a problem while connecting server using IE6 (this problem does not exist under FF 11 & Chrome (v16 or 17) & IE 9) :

Here is the connect system :
this.socket = io.connect('192.168.0.20/chat', {
'reconnect': true,
'reconnection delay': 500,
'max reconnection attempts': 1000,
'port': 8080
});

Under IE6, this result to a syntax error (property not exist, according to IE debug bar) :
//Line 1620
xhr.withCredentials = true;

I also add that's there is no site scripting (both index.html and socket.io are under 192.168.0.20)

[Deisss]

forgot to say : socket.io latest version (0.9.5)

[Gyaguchi]

I also detected the same problem too.
Environment (socket.io version：0.9.6 and using IE6)
as for the cause, IE6（ActiveXObject('Microsoft.XMLHTTP')） is not supporting xhr.withCredentials.
Although it has avoided by the following patch, how about this?

--- a/socket.io/node_modules/socket.io-client/lib/socket.js
+++ b/socket.io/node_modules/socket.io-client/lib/socket.js
@@ -148,7 +148,9 @@
       var xhr = io.util.request();

       xhr.open('GET', url, true);
-      xhr.withCredentials = true;
+      if (xhr.withCredentials) {
+       xhr.withCredentials = true;
+      }
       xhr.onreadystatechange = function () {
         if (xhr.readyState == 4) {
           xhr.onreadystatechange = empty;

[Jedius]

have same problem.. this patch let avoid error message, but any events in ie6 just not work.

my code:

server:
io = require('socket.io').listen(app)
io.configure ->
.. io.set("transports", ["xhr-polling"]);

io.sockets.on "connection", (socket) ->
.. console.log 'connected'

client:
socket = io.connect("http://192.168.1.3:4500")
socket.on 'connect', ->
.. alert 'connected'

in result, i see 'connected' on the server, but not alert in ie.

logs:

debug - served static content /socket.io.js
debug - client authorized
info - handshake authorized 3510702431436887415
debug - setting request GET /socket.io/1/xhr-polling/3510702431436887415?t=1335621627442
debug - setting poll timeout
debug - client authorized for
debug - clearing poll timeout
debug - xhr-polling writing 1::
debug - set close timeout for client 3510702431436887415
connected

bad news is that 30% сhinese use ie6, as said my client, and it's necessary for him. building 2 synchronous chats (with socket and without) is nightmare =\

[stevegeek]

Try using JSON-P polling instead of XHR polling

[Jedius]

It works, thanks!

[Krinkle]

Karma uses transports = ['websocket', 'flashsocket', 'xhr-polling', 'jsonp-polling']; by default. That includes jsonp-polling.

socket.io (more specifically nowadays, engine.io) says it supports browsers "as low as IE 5.5". Ideally that means it works out of the box and not require users hardcode transports = ['jsonp-polling'] based on some feature test, UA sniffing or even unconditionally.

See also karma-runner/karma#983.