use the extension library but error?

What should I do to solve this problem? Are there any examples of use that can be referred to?

This is the link between extension library and C,

I used VB 2010 compiled lua5.1 static library, and then compile my extension library mylib2, SZ extension library is someone else, there are JSON functions can be used:

Local SZ = require (“SZ”)

STR = “JSON”

Local a = {}

A = sz.json.decode (STR)

 

The function in my extension library mylib2 is written in C,any body can help me?