Or just use python with an interface

>>> import spam
>>> status = spam.system("ls -l")

#include <Python.h>
static PyObject *
spam_system(PyObject *self, PyObject *args)
{
    const char *command;
    int sts;

    if (!PyArg_ParseTuple(args, "s", &command))
        return NULL;
    sts = system(command);
    return Py_BuildValue("i", sts);
}

This also works fine, and maybe I will take this approach, or maybe a bit of both! But I can get this interface to join up and running rather quickly, and I will. Thus delaying any more work on shell.