Question

lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf);

Sets a new panic function and returns the old one.

If an error happens outside any protected environment, Lua calls a panic function and then calls exit(EXIT_FAILURE), thus exiting the host application. Your panic function may avoid this exit by never returning (e.g., doing a long jump).

The panic function can access the error message at the top of the stack.