How to determine application architecture in terminal

Question

I'm wondering how Finder determines on which architecture an application is able to run.
Using ditto --arch it is possible to extract PPC, PPC64 and i386 from a Mach-O application.
But HOW can Finder tell that an application ist Classic ? Or is it also possible to determine Motorla 68000 architecture in old classic fat binarys ?
I'm interested in that because I've got an iMac Core Duo that does not support classic any more and I want to find all classic apps on all my Fire Wire harddrives.
thanks in advance
Michael
iMac Core Duo 20"   Mac OS X (10.4.5)  

Answer 1

Hi Michael,
   The UNIX utility, "file" can distinguish between Cocoa and Carbon apps in many cases. Carbon apps usually return "header for PowerPC PEF executable". Compiled objective C, C++, and C executables return "Mach-O executable <Architecture>". Compiled Java classes return "compiled Java class data". Carbon apps for MacOS X return the same thing as classic applications. While they are almost the same thing, there are differences and I don't know how to spot them.
   Of course Cocoa applications are usually inside application bundles and if you apply the "file" utility to the containing directory, you will of course get an answer of "directory". You must apply file to the executable inside the bundle. The main one is always inside the Contents/MacOS subdirectory and always has the same name as the bundle, minus the ".app" suffix.
Gary
~~~~
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