Thank you Jason. This worked for me. I tested it in both the command line via /Applications/Wolfram.app/Contents/MacOS/wolfram and in a notebook. It is a "pure" journal file in the way I asked for. Will be adding it to my bag of tricks.

It would be nice if the command-line app "logged" like this automatically. In days gone by, my most productive way of working with software in general was a cycle of (working interactively, generating a journal file, using a text editor to improve and format that file, then read it back into the interactive application) and repeat. GUI apps took that ability away for the most part. But the generality and power of a good text editor is still unsurpassed for many jobs.

I used it with CreateFile.