[nodejs] Accessing an object wrap from c++ addon

Hello,

I'm developing a C++ addon and I'm trying to access the object wrap of a
unix stream net.Socket. Basically what I'm doing is:

1) in C++ land

/* The first argument of the function is the socket */
Local<Object> obj = args[0]->ToObject();
if (obj->InternalFieldCount() > 0) {
PipeWrap* wrap = static_cast<PipeWrap*>(obj->**
GetPointerFromInternalField(0)**);
}

2) in JS

var socket = new Socket(fd); // fd is a file descriptor of an already
created unix socket
my_function(socket); // call my_function implemented in the C++ addon

The problem I'm having is that the object internalFieldCount is 0. Any
ideas of what I'm doing wrong?

Thanks in advance.

Santi

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