More TODO resolution and cross-OS behavioral parity fixes.

new/main_darwin.m

@@ -21,6 +21,5 @@ void uiQuit(void)
 		subtype:0
 		data1:0
 		data2:0];
-	[NSApp postEvent:e atStart:NO];		// let pending events take priority
-	// TODO really wait?
+	[NSApp postEvent:e atStart:NO];		// let pending events take priority (this is what PostQuitMessage() on Windows does so we have to do it here too for parity; thanks to mikeash in irc.freenode.net/#macdev for confirming that this parameter should indeed be NO)
 }

new/main_unix.c

@@ -8,7 +8,16 @@ void uiMain(void)
 	gtk_main();
 }
 
-void uiQuit(void)
+// gtk_main_quit() may run immediately, or it may wait for other pending events; "it depends" (thanks mclasen in irc.gimp.net/#gtk+)
+// PostQuitMessage() on Windows always waits, so we must do so too
+// we'll do it by using an idle callback
+static gboolean quit(gpointer data)
 {
 	gtk_main_quit();
+	return FALSE;
+}
+
+void uiQuit(void)
+{
+	gdk_threads_add_idle(quit, NULL);
 }