How do Un-Installers work?

[Solomon Oppenheimer]

I am trying to understand how AppDelete, AppZapper, App Clean/er, Remove-It and any such Un-Installers work.

I'd like to know how they detect and locate all the files that are associated to a certain app.

Is there a standard command one could use in Terminal to achieve the same thing, namely listing all files belonging to, generated by, associated to a certain application? Anything special in macOS that defines a relationship between apps and their files?

Or do the uninstaller apps simply search and hope to find everything that belongs to a certain application, like...:

find / -iname "*Mail*"

Apparently not, as trying to locate files related to e.g. Apple's own Mail app results in a LOT of files, most of which have nothing to do w. Mail

Remove-It (previously know as 'iTrash') claims to use some Levenshtein Distance search algorithm to find files - so do in the end all do a (more of less sophisticated) search?

How does it work? Can it all be achieved in Terminal? How?

Many thanks in advance for some explanation and enlightenment

 

[StellarVixen]

Uhm…because they know where to look. They look for the folders associated with the app name and delete them as well from the Library.

Every app (at least legit non malicious app) follows a set of rules where it can write its necessary stuff, so these folders and files are always found in the same places.

 

[Solomon Oppenheimer]

Uhm…because they know where to look. They look for the folders associated with the app name and delete them as well from the Library.

How do they know where to look? Yes, obviously they look for files and folders associated with the app name and delete them from Library and other places, but how do they do that?

Every app (at least legit non malicious app) follows a set of rules where it can write its necessary stuff, so these folders and files are always found in the same places.

What are these rules? Do they generally apply or can every App define own rules on where it wants to write its stuff?

 

[Fishrrman]

Is there a particular reason WHY you need to know how these apps do what they do?

I use AppCleaner because it seems to work the best.

 

[Solomon Oppenheimer]

Is there a particular reason WHY you need to know how these apps do what they do?

Besides pure curiosity, I have a problem w. moving Mail to my new Mac and I thought maybe there is a special way to find all files related to Mail?
Yes, also I use primarily AppCleaner (besides others) but the lists of files they generate didn't work for the particular purpose - you already commented in this thread...

 

[Weaselboy]

Besides pure curiosity, I have a problem w. moving Mail to my new Mac and I thought maybe there is a special way to find all files related to Mail?

I would export the mail from the old Mac then copy the exported files to the new Mac then import.

Trying to do it in Finder is just going to muck things up if you don't know exactly what to copy.

 

[Solomon Oppenheimer]

I would export the mail from the old Mac then copy the exported files to the new Mac then import.

Thanks Weasel. I tired that, and w. 20+ Mail accounts I needed to not only export 20+ inboxes, but also 20+ folders of sent mail, plus 30+ Local Folders, smart mailboxes and whatnot. Accounts were not moved and had to be set up from scratch, and, and, and.

But even after I did all that, import went belly up and threw an error at 60% of import. 😑

So I hoped it would somehow be possible to copy all files that somehow belong to Mail, but as it seems you are right and things get mucked up: if I rely on the lists of files identified by the Un-Installers Mail on the new Mac doesn't "see" nothing of what I copied over... 🤷🏼‍♂️

 

[Fishrrman]

"But even after I did all that, import went belly up and threw an error at 60% of import."

What this suggests to me is that one (or more) emails (or attachments to those emails) is corrupt, and that this is causing the entire process to abort.

Do you have an external drive available?
I could suggest an alternate course of action.