[Timber]

Yes, it's inside of the Calibre.app package under contents. No argument there.

Issuing this command from the terminal will call it on a mac "/Applications/calibre.app/Contents/MacOS/ebook-viewer ; exit;"

You can also get to it by going into applications, right clicking on calibre.app, choosing show package contents and the selecting ebook-viewer.

However that's not how file associations are done on a mac. When you click on a file to choose which app to associate with it, your choices are recommended apps or all apps.

They have to be the actual .app packages such as calibre.app or ibooks.app to be associated with file extensions. You can't associate a file extension with something that's within a .app's package contents, as in the case of the ebook-viewer being a component of calibre.app

If that makes sense, what I'm trying to say is that mac users can associate the main calibre app with various ebook file extensions, but cannot associate them with the ebook-viewer subcomponent.

That's why I was asking If it was possible for ebook-viewer to be a separate .app of it's own, in addition to how it's a component of calibre.app, because then mac users could use it to associate with ebook file types.

However, since it's not a .app by itself, mac users can't associate it with the ebook types. Clicking an ebook will call the main app, not the ebook-viewer.

Hope that better explains what I was asking. I understand very clearly how to get to it, but can't use it for file associations as a subcomponent of an .app. Can only associate with .apps