hello,i don't understand .{"_placeholder":true,"num":0} what is that mean?

[fcy197778770]

i can't Received anything and i dont khow why
THX

[miguelgrinberg]

This is an aspect of the Socket.IO protocol. If you are interested in this level of detail, consult the Socket.IO protocol documentation.

Your binary data is in the packet that follows right after the one you highlighted.