How do you convert a C struct to JSON using the JSON-C library?

Having come across the same issue, i wrote a library that helps with this problem. https://github.com/jamie-pate/jstruct . You can annotate existing c structures, and a python script generates meta-data c headers based on the annotations. The library reads the metadata to import/export c structures to json strings and back. A python script takes care of parsing the annotated header and generating new headers and metadata initializers. The jstruct library uses https://github.com/json-c/json-c  internally.I have also noticed https://github.com/marel-keytech/jsoncc but that was after writing the entire thing. (and info on that project's page is sparse)