I prefer a simplified DBSTACK solution:

function flag = isMultipleCall()
   s = dbstack();
   flag = (numel(s) > 2) && (sum(strcmp(s(2).name, {s.name})) > 1);
end

I also used a solution almost similar to Arda’s (using a persistent variable). After reading this post I opted for the isMultipleCall() because, like Malcolm very very wisely says, I had problems when internal callback errors (which were not fatal in my case) or Ctrl+C stopped the callback that I was controlling for recursive call. In this case the callback could not be run again unless I explicitly cleared all variables.

I’m confused on one count though, and I’m sure this is just my lack of understanding of how Matlab runs behind the scenes. Why does this not work with a figure’s ResizeFcn callback? I would really like to have a custom resize, but it needs to be safe against re-entrancy. Currently, I’d handle this with a timer, but I’d rather not have to use that.

Is there a way to get this to work with the ResizeFcn?

Thanks.

@Rafael – if the callback’ed object supports the BusyAction and Interruptable properties, then setting these would be the easiest choice. Otherwise, you could preserve the callback parameters in some persistent data struct (e.g., a cell array) and set a timer object to run the callback function programmatically in a second or two.

@Yair – Thank you very much for the quick reply, I’ll definitely give it a try.

@Michele – you could store a temporary flag in a persistent variable or the handle’s ApplicationData/UserData, or a variant of these. For example:

% Variant1
function myCallbackFcn1(hObject,eventData,varargin)
   persistent inCallback
   if ~isempty(inCallback),  return;  end
   inCallback = true;
   try
       % do something useful here
   catch
       % error trapping here
   end
   pause(0.001); drawnow;  % give all other events a chance to bail out above
   inCallback = [];
end  % myCallbackFcn1

% Variant2
function myCallbackFcn2(hObject,eventData,varargin)
   inCallback = getappdata(hObject,'inCallback');
   if ~isempty(inCallback),  return;  end
   setappdata(hObject,'inCallback',true);
   try
       % do something useful here
   catch
       % error trapping here
   end
   pause(0.001); drawnow;  % give all other events a chance to bail out above
   setappdata(hObject,'inCallback',[]);
end  % myCallbackFcn2