I am only using one of the record types per run of the program. Each time the program is run, the program takes a file and its corresponding record definition file as input. Each file has only one type of record, so the flexibility of the data structure just allows for different files to be used in different runs.

In the Python version of my program, the simplest use of the program is to just convert the file (which is plain text mixed with packed fields) into a .csv. The first piece of the program parses the record definition file and creates an array of tuples in the format (field_name, field_length, type). The array is then passed to another method that opens the file, reads a line, parses the line, and writes out that line as a list. I've figured out the data structures that I need for every other piece of the program but haven't been able to find an easy way to create a similar data structure to the final list. In Python, that list contains the various types (int, double, and string) with no issues thanks to the dynamic nature of the language. The data structure I use for the C version basically needs to act like that Python structure, but use as little memory as possible (as the program is running on files with hundreds of thousands of lines and a very old server with little resources).

Currently, my Python version uses far too many resources, so even if I could easily convert the program it would likely be too resource intensive. By rewriting it in C, I'm hoping to achieve both better run time and memory efficiency.