Many people (including me) have advocated such a system in this forum to give all kinds of trojans (see for instance the thread about the recent trojan proof-of-concept) and other virus-like apps a harder time. What you want is a new layer of file security on top (which would need to be implemented in the kernel) that gives much more fine-grained control over file access. The application you are looking for is called 'kernel' and it uses Unix permissions to determine whether an application can access a file. What I'm looking for is something that blocks a process rather than finding out after-the-fact that an application read in a file it shouldn't have. Little Snitch runs inconspicuously in the background and it can also detect network related activity of viruses, trojans and other malware. Little Snitch Mini 4+ Enjoy your privacy Objective Development Free Offers In-App Purchases Screenshots As soon as you’re connected to the Internet, your apps can send whatever they want to wherever they want, unnoticed by you, because all of this happens invisibly under the hood.

Quote:Originally posted by spacehaven:lsof will show what files are currently open. Open the Mac App Store to buy and download apps.

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