I was wondering if this is possible, and if so how to do it?
cross-compiling mac files from a linux machine
Well JayBird bought a MAC for it, so I think it is not possible. Really just a guess though.
Nobody ever took the time to create cross-compiler for Mac running in Linux. The problem is that you’d need to reverse-engineer the Mac C libraries because those differ quite a lot from the GNU libraries.
So you’ll have to ask someone with a Mac to compile it for you, or buy yourself a Mac Mini. (Bani did, if I’m not mistaken.)
It’s tricky. You still need a copy of the Mac OS, and then you need to get a Mac emulator (google it, easy find). There are many programs to emulate a Mac on WIndows/Linux, all you really need are the headers from the OS.
Otherwise just get someone to pull you in a favour (I would suggest when you get everything working just fine before your final release, they won’t want to compile it 50 times
)
Yes, it is now possible…
http://ranger.befunk.com/fink/darwin-cross/
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He has a good point though, you can get a good enough Mac on Ebay for 30 bucks (not joking, they are really quite cheap if you just look and wait for a week or two).
Combined with mac emulator:
http://www.emulators.com/
http://www.thefreecountry.com/emulators/macintosh.shtml
One I actually heard something about that sounded not half bad:
http://pearpc.sourceforge.net/
Maybe these help the cause??
not quite.
http://www.emulators.com/ emulates this:

pearpc is unusably slow (1/500 native speed). you still need to buy osx ($130).