yes, the gcc complains about the code produced by mprep, but this is a warning only and no error . On my MacBook I get the same warning, when I use gcc, still the MathLink program runs fine.
Did you check to start the the "image" program from the command-line and give it a link-name like "blub" and try to install this link by
lnk = Install[LinkConnect["blub"]]
inside Mathematica? If this runs, then your DYLD_LIBRARY_PATH is maybe not usable inside Mathematica. In this case you have to create/adjust your ~/.MacOSX/environment.plist file so that GUI-programs like Mathematica have a correct DYLD_LIBRARY_PATH. See here  how to do that.
 You may know the famous joke: A guy is standing on the corner of the street smoking one cigarette after another. A lady walking by notices him and says "Hey, don't you know that those things can kill you? I mean, didn't you see the giant warning on the box?!" "That's OK" says the guy, puffing casually "I'm a computer programmer" "So? What's that got to do with anything?" "We don't care about warnings. We only care about errors."
On Sun, 2012-02-26 at 04:22 -0500, Murray Eisenberg wrote: > Compiling as you showed worked just fine to produce the MathLink > executables 'delaunay' and 'contour.' > > However, there were compiler warnings when I applied gcc for both > 'image' and 'mandelbrot', as follows (where i use "\" for continuation > of input because the long command line input won't fit on a single line > here: > > $ $MLROOT/mprep image.tm > image.tm.c > $ gcc -o image -I$MLROOT -L$MLROOT -lMLi3 -lstdc++ -framework \ > Foundation -lm image.tm.c > image.tm.c: In function =91sendimage=92: > image.tm.c:308: warning: incompatible implicit declaration of > built-in function =91malloc=92 > image.tm.c:321: warning: incompatible implicit declaration of > built-in function =91sprintf=92 > image.tm.c: At top level: > image.tm.c:344: warning: prototype for =91sendimage=92 follows > non-prototype definition > > $ $MLROOT/mprep mandelbrot.tm > mandelbrot.tm.c > $ gcc -o mandelbrot -I$MLROOT -L$MLROOT -lMLi3 -lstdc++ -framework \ > Foundation -lm mandelbrot.tm.c > mandelbrot.tm.c:402: warning: prototype for =91sendimage=92 follows > non-prototype definition > > And then, of course, when I load either ExtendGraphics`Image` or > ExtendGraphics`Mandelbrot`, I get an error: > > LinkOpen::linke: Specified file is not a MathLink executable... > > Can you suggest how to fix this. Or, in the alternative, supply > Macintosh OS X versions of the executables 'mandelbrot' and 'image' > (compatible with current OS X versions). > > On 2/20/12 2:44 AM, Patrick Scheibe wrote: > > Hi Murray, > > > > did you try to compile this by yourself? Here on Linux it builds fine > > and it does not need any Solaris library. The paths in the "build" file > > are outdated. That's why you cannot simply use it. Try it on the > > commandline by yourself. What you have to find is the MathLink dev > > directory in your Mathematica installation. Here it is under > > > > /usr/local/Wolfram/Mathematica/8.0/SystemFiles/Links/MathLink/DeveloperKit/Linux-x86-64/ > > > > I assume on your machine it will be under something like > > > > /Applications/Mathematica.app/SystemFiles/Links/MathLink/DeveloperKit/CompilerAdditions/ > > > > Let's say this path is $MLROOT, then you have to do the following: > > > > $MLROOT/mprep delaunay.tm> delaunay.tm.c > > gcc -o delaunay -I$MLROOT -L$MLROOT -lMLi3 \ > > -lstdc++ -framework Foundation -lm delaunay.tm.c > > > > (Remove the backslash and input the last two lines as one!) > > This should compile fine the delaunay-triangulation and should work for > > all the other programms too. > > > > Cheers > > Patrick > > > > > > On Sun, 2012-02-19 at 06:29 -0500, Murray Eisenberg wrote: > >> Many years ago, Tom Wickham-Jones wrote a book, "Mathematica Graphics:= > > >> Techniques& Applications", which I own. It was accompanied by the > >> ExtendGraphics application, which included nice packages for drawing the > >> Mandelbrot set and Delaunay set, among other things. > >> > >> The application is also available at: > >> > >> http://library.wolfram.com/infocenter/Books/3753/ > >> > >> But they don't work with Mathematica 8, at least under Mac OS X. The > >> .zip download includes Windows .exe binaries; the .tar download includes > >> ingredients for compiling binaries (including a "build" file, but the > >> build fails under OS X due to missing libraries from Solaris). > >> > >> Anybody have a version of the requisite binary files that work with > >> current Mathematica under OS X 10.7 (Lion)? > >> > > > > > > > > -- > Murray Eisenberg email@example.com > Mathematics & Statistics Dept. > Lederle Graduate Research Tower phone 413 549-1020 (H) > University of Massachusetts 413 545-2859 (W) > 710 North Pleasant Street fax 413 545-1801 > Amherst, MA 01003-9305 > >