receiveFd
Receives a file descriptor from the sending end of the connection. The sending end has to call g_unix_connection_send_fd() for this to work.
As well as reading the fd this also reads a single byte from the stream, as this is required for fd passing to work on some implementations.
Return
a file descriptor on success, -1 on error.
Since
2.22
Parameters
cancellable
optional #GCancellable object, null to ignore