Actually, assuming you have Tk ( a reasonable assumption, now that there is a) a rootless XFree86 build available and b) a dylib of Tk that runs under X-Windows), one could simply compile the 'gui part.'
As far as the base, I would start with Karl MacMillan's FreeBSD port. (I have to admit, I haven't seen his port; my comments are based on the IRIX version, from around 0.32. But, the Mac OS UNIX layer is based on 4.4BSD, so his version would be the closest) You need to rewrite the module loading section to use dylib, and alter some timing related things in the scheduler.
Then, one could use CoreAudio/CoreMIDI for the audio and MIDI portions.
So, I guess the answer to your question is: the base part.
florian wrote:
especially, wouldnt it be possible to port it to mac os x? what is the most problematic part to port? the 'base part' or the 'gui part'?
as far as the 'gui part' goes, what ever happened to the gtk gui?
Well well, that raises the following question: Would it be too difficult to port pd to the MacOS system?
Using portaudio there would at least be a common audio layer for different kinds of platforms....
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