SBJSON append new data into existing JSON file without parsing it first
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I am making an app that lets the user draw on the screen in different colors and brush sizes.  I am storing the info about each drawn path in a JSON file once it has been drawn to keep it out of memory.  Right now I have it parsing all existing paths, then adding the new one in and writing it all back out again.  I want it to simply append the new data into the JSON file without having to read it in and parse it first, that will make it so only one path is ever in memory at a time.  

I am using SBJSON, the JSONWriter has a few append functions but I think you need to have the JSON string to append it to first, not the file, meaning I would have to read in the file anyway.  Is there a way to do this without reading in the file at all?  I know exactly how the data is structured.