On 28 Jun 2009, at 02:13, Stefan Blixt wrote:
OSX has the ability (inherited from NextStep I think) to treat whole directories as applications, so you can click the directory icon and have its application start. E.g. in the Applications folder I see Safari in Finder, but if I open a terminal and cd there I see a directory called Safari.app, containing an application structure. I thought this was only a gui thing, but maybe there is some deeper connection with resources and stuff even to simple executables like the chuck program. I find this unlikely though - especially since the chuck executable does not have this kind of .app structure.
It is only a GUI thing, plus Mac OS X system components implemented on top of the underlying UNIX/Mach structure, at least in 10.5 and later. The Application bundle contains an ordinary program which the Finder launches, with an argument that perhaps is used to identify it for AppleEvents and such. Try repeating in Terminal /Applications/Calculator.app/Contents/MacOS/Calculator & You get several copies of the Calculator program running. Hans