I'm trying to create a "save as" dialogue for an application I'm writing.

I have a sketch that currently writes output erratically (in terms of intervals between writes) to a text file using createWriter, but I want to bring it under the control of a timer. I
The sketch works fine until I add some variant of:

1. if (millis() % 100 == 0){
2.      output.println("text" + millis());
3. }

or

1. if (frameCount % 10 == 0){
2.      output.println("text" + millis());
3. }
   

into

1. void draw():

then it doesn't write to file at all.

The rest of the code works fine, it's just this one conditional that I don't understand/can't get to work.
I got the framework for what I'm doing in the code above from an included example (file IO =>  SaveFile2) and then the excellent blog post here: http://amnonp5.wordpress.com/2012/01/28/25-life-saving-tips-for-processing/