I've written some code to query the networkAccessible state and on Windows, it is always QNetworkAccessManager::UnknownAccessibility even if the associated QNetworkAccessManager object is creating successful connections (or even if I disable all network interfaces on the system). I've looked through the QNetworkAccessManager code but can't figure out how this is set. Does anyone know what the OS must report for this to work? I realize that you can also explicitly set the state for a given object but that is not what I'm interested in.
Looking at the code it appears to be based on the bearer management apis like QNetworkConfiguration. See http://qt.gitorious.org/qt/qt/blobs/4.7/src/network/access/qnetworkaccessmanager.cpp#1352