How return an object of a struct from c to Mathematica?

Question

I'm writing a c code by using WSTP library. In my c codes, I have a struct named Person, and I have a function named Foo, which returns an object of Person.

struct Person
{
   int id;
   char* name;
};

Person* Foo()
{
   Person* person = new Perosn();
   ...
   return person; 
}

My problem is in the .tm file, I don't know how can I determine the return type. Please guide me.

Answer 1

In file.tm, you need to set the return type to Manual, and declare your C(++) function to be void.

Then return each piece of data making up the struct separately, using low-level MathLink functions.

In this case, you could return a List of an integer and a string, i.e. use

WSPutFunction(stdlink, "List", 2);
  WSPutInteger(stdlink, person->id);
  WSPutString(stdlink, person->name);

at the end of the function.