Sound idea, well done.
Personally I would use Python, as virtually every RPI H/W supplier ships their libraries in Python. Its emerging as the language of choice for so much in the RPI world. I used to cut C and Perl for decades. Now all I use is Python.
There are Python libraries to create Open Office calc files, Excel and most other spreadsheet formats. At very least creating a CSV file is easy without any additional libraries.
Be sure your code deduplicates the NFR reads. NFR is notorious for multiple reads with one swipe.
..the only thing worse than a stupid question is a question not asked.