build.sh

#!/bin/sh
clang -c -I/Users/nasser/Scratch/unity-mono -F/Library/Frameworks ForceEditorUpdates.m
libtool -dynamic -framework Mono -o ForceEditorUpdates.dylib -macosx_version_min 10.9 -undefined dynamic_lookup ForceEditorUpdates.o
cp ForceEditorUpdates.dylib ForceEditorUpdates.bundle

ForceEditorUpdates.m

#include <Cocoa/Cocoa.h>
#include <mono/metadata/appdomain.h>
#include <mono/metadata/assembly.h>
#include <mono/metadata/image.h>
#include <mono/metadata/class.h>
#include <mono/metadata/object.h>

// http://www.jerrodputman.com/2010/01/10/the-unityobjective-c-divide/

MonoMethod *update_method;

void call_update_functions() {
  mono_runtime_invoke(update_method, NULL, NULL, NULL);  
  
  dispatch_after_f(
    dispatch_time(DISPATCH_TIME_NOW, 100000000),
    dispatch_get_main_queue(),
    NULL,
    call_update_functions);
}

// we do what we must
void StartForcingEditorApplicationUpdates() {
  MonoDomain *domain = mono_domain_get();
  // TODO better assembly lookup
  MonoAssembly *assembly = mono_domain_assembly_open(domain, "/Applications/Unity/Unity.app/Contents/Frameworks/Managed/UnityEditor.dll");
  MonoImage *image = mono_assembly_get_image(assembly); 

  // TODO use our own update method to avoid double invoking Internal_CallUpdateFunctions
  MonoClass *klass = mono_class_from_name(image, "UnityEditor", "EditorApplication");
  update_method = mono_class_get_method_from_name (klass, "Internal_CallUpdateFunctions", 0);
  
  dispatch_after_f(
    dispatch_time(DISPATCH_TIME_NOW, 100000000),
    dispatch_get_main_queue(),
    NULL,
    call_update_functions);
}