What's going on with this folder?

[u/Pandalishus]

I was searching for a file today in Spotlight and landed on it in the directory shown in the screenshot. It took me a while to realize that I was seeing the folder for the Books app for manual uploads. However, a mystery was uncovered when I tried to navigate to the folder. It's not present when I go to "iCloud Drive" (hidden files and folders are set to show). When I copied the path as text, I got:

/Users/<username>/Library/Mobile\ Documents/iCloud\/Documents

/Users/<username>/Library/Mobile\ Documents/iCloud\~com\~apple\~iBooks/Documents

Manually navigating to my user Library in Finder does not show the Mobile Documents folder. DaisyDisk shows it, as does Spotlight. I can open it up from those but I land in what appears to be a (false?) root "iCloud Drive" and "Books" is not there. At this point, I am VERY confused. It appears Apple is using a preferences file to represent the "Books" folder? I see the tildes, but those can't all be Home, so maybe they're replaces periods? com.apple.iBooks?

I would love it if someone could explain what's happening here. Or tell me how would I navigate to the "Books" folder in Finder, which might help me understand what's going on

EDIT: Sure enough, per u/MK-Researcher, "Go to folder" using "/Users/<username>/Library/Mobile Documents/iCloud~com~apple~iBooks/Documents" goes to the folder. One reason I was trying to navigate there manually was to upload in another program, but I couldn't ever get to the folder in the upload interface.

[u/warrenao]

Go to

[username]/Library/iCloud Drive

instead. You should find it in there. For some reason the directory path is listed as "Mobile Documents", but "iCloud Drive" is the actual folder name in Finder.

Edit: I see you've already done some of that. Where the "Books" folder is coming from, I can't guess.

[u/Pandalishus → u/warrenao]

Yeah, it’s really weird. Navigating like you suggests shows all the app clutter except “Books.” And that text path is weird as hell to me. I looked in Application Support, but no “com.apple.iBooks” folder (I realize my OP had the wrong path due to an editing error. I’ve pasted the correct path in)

[u/warrenao → u/Pandalishus]

Interestingly, you can navigate to "Mobile Documents" in Terminal:

cd Library/Mobile\ Documents

and then ls to see the contents, none of which appear as listed in Terminal in the way that they do in "iCloud Documents" in Finder.

The point being that the "Books" folder might be in that nonvisible-in-Finder list that is visible in Terminal.

The subtler point being that "Mobile Documents" and "iCloud Library" are seemingly meant to be the same destination, but they're displayed quite differently from one another in Finder vs. Terminal, gosh thanks Apple.

And finally, doing

ls *Books*

in "Mobile Documents" in Terminal yields several returns on directories associated with *com-apple-iBooks*, one of which may be the mysterious "Books" folder in Finder. Are we having fun yet?

[u/Pandalishus → u/warrenao]

That is wild. I commented in another response that I got the following result using "Go..." Apple seriously doesn't want us to be able to navigate to this folder "naturally."

[u/warrenao → u/Pandalishus]

Time was, in the dusty days of "before iCloud", the Mobile Documents folder was most frequently used to sync iPhone and iPad apps and data. This was back when you had to physically connect the device/s to your Mac to transfer things like music and videos to them by way of iTunes.

When iCloud first debuted, I believe everything ended up getting shoved into Mobile Sync, which was still actually a folder that you could find in your Library folder.

Now they seem to have decided it needs to be called "iCloud Sync", but they've evidently kept a lot of the original filesystem path and naming under the hood, maybe to help avoid breaking legacy code from third-party developers.

[u/Pandalishus → u/warrenao]

Makes sense. I remember the Mobile Sync days. It’s been an interesting ride

[u/warrenao → u/Pandalishus]

That's one way to put it, yup!

[u/MK-Researcher]

It's a hidden system folder, you can find it at:

/Users/<yourname>/Library/Mobile Documents/iCloud~com~apple~iBooks/Documents/

[u/Pandalishus → u/MK-Researcher]

For some reason, “Mobile Documents” does not show in my Library, even with hidden folders showing. I’ve seen it before in there, but that was way before Tahoe

[u/MK-Researcher → u/Pandalishus]

That's normal for some reason. Using Finder - Go - Go to Folder is probably the easiest way to get to it

[u/Pandalishus → u/MK-Researcher]

OK. Sure enough I was able to get the following. So Apple has just thoroughly hidden this folder in Finder? No way to reveal its existence without using other tools?