Maybe I have not made clear what I try to accomplish: I do not want to add another format, and did not asked for detailed command-lines. I just want to replace a present book in the same format because its source (LibreOffice, Asciidoc etc.) has changed. To do this an id is required.
Here is explained: "You can get id by using the list command."
But as I posted by example the output of this command is hard to parse, and also the title from the newly added files must be known to extract the id from the
list output.
Nevertheless I tried adding the book and parse the messages: no luck. As you showed, it only tells the id when adding a new book. When the book already exists it just prints an error. And with
--duplicates it prints the new id.