Wow, it was that simple. I had glossed over the intro in the examples and went straight to focusing on the code... I'll slow down next time and read things more carefully.
I changed the filename variable declaration to char filename[12] = {0}; and things worked just fine.
One question, should my character array buffer be 13 instead of 12?
It seems to work just fine with a buffer of 12 bytes, but I was under the impression that it's a good practice to have one extra byte in a buffer in C.
Thank you for having me think through the problem a little.
I really appreciate your help!