netvfy-agent fails to start if HOME is not set: "ndb_init: stat"

[orwell96]

Operating System: Raspberry Pi OS (aka. Debian Buster)
Install method: apt-get

I was setting up a systemd service for netvfy. For this purpose, I provisioned the node using the root account and made a simple systemd service unit. Starting this unit failed with the rather unintuitive error message

ndb_init: stat

However, starting from the command line worked normally.

By looking at the code (specifically here), I suspected that it failed because of a missing HOME env variable.

Using this command line instead did the trick:

env HOME=/root netvfy-agent -c Network

To prevent confusion for future users, I suggest adding a more informative error message when stating the directory fails, and/or explicitly checking whether the HOME environment variable exists and outputting an appropriate error message.