Octave exists during the call "QApplication application (argc, argv);" at line 87 in libgui/src/octave-gui.cc
80 int
81 octave_start_gui (int argc, char *argv[])
82 {
83 dissociate_terminal ();
84
85 setenv ("GNUTERM", "qt", 1);
86
87 QApplication application (argc, argv);
With lack of experience with c++, I don't know how to go further.
It looks like yet another hard limitation of Mac OS X. If Qt decides to exit the app, there's probably a good reason for it, and it's also probably difficult (or impossible) to work around as-is. You might try to debug further with debug version of Qt, but I'm not sure it's worth. Now I'm wondering what can be done to make it work under Mac OS X. Maybe we should simple re-exec octave with a specific flag to avoid re-forking?
Michael.