Network Accept tracker to handle empty address

If an application calls accept() with the addr argument set to NULL, then the remote IP address and port will be set to 0. The networkTracker::seenAccept() function needs to recognise this situation and look up the details in /proc using the file descriptor. If the connection isn't in /proc then it should return true with both addresses and ports set to 0, so that the received connection is still reported, even though the addresses and ports are empty.

A further enhancement would be to track calls to bind() and store the local address and port against the file descriptor, so that in the condition where addr is NULL, the local port can be used to match against the cache of connections.

Comienza en networkTracker::seenAccept() y sigue cómo accept() maneja un argumento addr NULL. Inspecciona la búsqueda en /proc mediante el descriptor de archivo y la ruta existente de notificación de conexiones; se considera terminado cuando las conexiones siguen notificándose con direcciones y puertos puestos a cero cuando no existe ninguna entrada en /proc. El seguimiento opcional de bind() es una mejora independiente.