This is strange!
The documentation on running the Bitcoin daemon on a Ubuntu machine is clear. The configuration file is supposed to be at $HOME/.bitcoin/ location. And yet, I cannot locate it! I looked for clues at /etc, /var, and /tmp too; nothing there. In fact, in one of my attempts to launch the daemon, the debug.log (created at $HOME/.bitcoin/) did call out the configuration file to be $HOME/.bitcoin/bitcoin.conf but the file itself wouldn't be listed. Permissions? - I don't know.
Can you please tell me where to look for this file?
This is on Ubuntu-16.04, 64-bit where bitcoin was installed via PPA. Yes; I am working with Bitcoin code for the first time.