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I’m trying to run a OpenGL program from the command line with:

cc -o hello -framework OpenGL -framework GLUT hello.c

It’s one of the first programs from TheOpenGLRedBook. I know I must be missing something because I keep getting:

ld: /usr/lib/crt1.o illegal reference to symbol: __objcInit defined in indirectly referenced dynamic library /usr/lib/libobjc.A.dylib

from the linker. Any suggestions?

I’m not sure, but I think GLUT on MacOS X is implemented on top of Cocoa. So perhaps you need to add “-framework Cocoa” to your command line?

Out of curiosity, is there a reason why you’re not just building and running from XCode or ProjectBuilder or whatever?

–Tom


Well it’s partly an attempt to improve my understand of OS X’s underpinnings. I’m reading Core Mac OS X and UNIX Programming by Dalrymple and Hillegass. Great book, so I decided I’d tackle it w/ only the command line and emacs. Call me crazy.

Anyways I solved the problem by sniffing around Apple’s porting from UNIX docs.

The source code should be compiled with:

cc -o hello -framework OpenGL -framework GLUT hello.c -flat_namespace

The program can then be launched just like any other command line program.

I hope somebody else finds this useful.


command line and emacs - that totally warms my heart! Glad you’re liking the book. ++MarkDalrymple


You can ditch the -flat_namespace flag (which I personally try to avoid) by adding -lobjc to your list of library flags.