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Comment by sirn | Hacker News Reader

Nice looking app! But why distributing it as PKG when it only creates Private Eye.app and com.radiosilenceapp.nke.PrivateEye.plist?

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It has to install the plist to /Library and launch the kext after installation. I'm not sure if that can be done just by sharing an .app bundle.

How did VMware Fusion 4 do it though? They just distributed the whole VM as a single .app, with all kexts loads/unload dynamically on launch.

Good question. I honestly have no idea. The kext has to be owned by root:wheel for the system to accept it. Making a pkg installer was the simplest solution I knew of.

Out of curiosity: is there a downside to pkg's?

VMware launches a sudo script to do it's deeds ..

I believe smcfancontrol installs its kext by demand from inside the Cocoa App. I don't know how it's done (I only do UNIX stuff on my Mac =/) but I believe it changes the .kext owner and invokes kextload. You can 'sudo' from inside a Cocoa App by using AuthorizationExecuteWithPrivileges:

http://michaelobrien.info/blog/2009/07/authorizationexecutew...

About PKGs: I think that they're okay, but, historically, they're maligned for being "black boxes" that install files all over your system. App files, OTOH, are (99% of the time) clean, live on /Applications, and sometimes use ~/Library.

The downside to packages (in users' minds) is that you have no idea where the pkg is going to install things, and also no idea how to clean it up later.

It's assumed that an .app, however, will remain self-contained.

VMWare and most applications that do this use Authorization Services. It's what pops up the dialog asking you to enter your password. Feels pretty magic to use it.

https://developer.apple.com/library/mac/#documentation/Secur...

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