I fired the Raspberry Pi/DVAP up and was pleased to find that all was ok. Since it was a few months since I updated the G4KLX DVAPNode and ircDDBGateway software. I thought I would get that done.
I ran the klxupdate utilities for both repeater and gateway software and then when I rebooted, I found thaqt although the ircDDBGateway software started, the DVAPNode software didn't! First of all, I couldn't see why, but then I tried
which returned a error message saying that libwiringpi.so could not be found
Initially, I thought perhaps I just needed to upgrade the OS, so tried the standard
sudo apt-get update
sudo apt-get upgrade
The upgrade took around an hour, but after that was completed, I tried to start dvapnode - still the same error!
Whilst the Pi was upgrading, I had plenty of time to research the issue a little more and found a page which described installing the WiringPi library
This was the solution! Following this, the DVAPNode software started just fine.
To my amusement, when the software started up, REF001C was very busy with a DSTAR contest!