Many think that a file’s type is determined by its extension. Although partly true, that’s indirect: it’s the UTI which sets the type, as explained here.
LaunchServices
Four popular and straightforward ways to set your Mac to run an app or other software when it starts up. Includes AppleScript code.
Where to see them, how they’re constructed, Apple’s rules, how they are created, and how even Apple doesn’t use them according to its own rules.
If you use the Installer app the wrong way, it will open an ad-hoc signed package and quietly install apps which don’t get checked by Gatekeeper.
You try to open an app on your M1 Mac, only to see an alert telling your that you don’t have permission to open it. Only that isn’t the reason.
How apps can opt to set the quarantine flag on files they create, and how macOS can override that to protect you.
They’re Base-64 encoded data which is related to the Finder Alias. Here’s how to resolve them in an app, at the command line, and in code.
An explanation of the magic which takes place when you double-click a document, the things that can go wrong, and how to fix them.
How to get all sorts of useful information about a running app or process from LaunchServices: and introduction to using lsappinfo.
A quick tour of this unique utility, and a recommended update for it which brings control over text size, auto-updates, and more.
The Eclectic Light Company 