title: On Linux: how can I programmatically determine if a NIC interface is enabled and plugged in?
body: <p>I want to determine if a network card is enabled, up, and plugged in. Basically, I want to know if the network card will work. I need this information from with a C++ program, and would like to display an error message when the network isn't working properly. If possible I would like to avoid using shell commands to determine this information.</p>