cpython/Demo/embed/demo.c

/* Example of embedding Python in another program */

#include "Python.h"

PyObject* PyInit_xyzzy(void); /* Forward */

main(int argc, char **argv)
{
	/* Ignore passed-in argc/argv. If desired, conversion
	   should use mbstowcs to convert them. */
	wchar_t *args[] = {L"embed", L"hello", 0};

	/* Pass argv[0] to the Python interpreter */
	Py_SetProgramName(args[0]);

	/* Add a static module */
	PyImport_AppendInittab("xyzzy", PyInit_xyzzy);

	/* Initialize the Python interpreter.  Required. */
	Py_Initialize();

	/* Define sys.argv.  It is up to the application if you
	   want this; you can also let it undefined (since the Python 
	   code is generally not a main program it has no business
	   touching sys.argv...) */
	PySys_SetArgv(2, args);

	/* Do some application specific code */
	printf("Hello, brave new world\n\n");

	/* Execute some Python statements (in module __main__) */
	PyRun_SimpleString("import sys\n");
	PyRun_SimpleString("print(sys.builtin_module_names)\n");
	PyRun_SimpleString("print(sys.modules.keys())\n");
	PyRun_SimpleString("print(sys.executable)\n");
	PyRun_SimpleString("print(sys.argv)\n");

	/* Note that you can call any public function of the Python
	   interpreter here, e.g. call_object(). */

	/* Some more application specific code */
	printf("\nGoodbye, cruel world\n");

	/* Exit, cleaning up the interpreter */
	Py_Exit(0);
	/*NOTREACHED*/
}

/* A static module */

/* 'self' is not used */
static PyObject *
xyzzy_foo(PyObject *self, PyObject* args)
{
	return PyLong_FromLong(42L);
}

static PyMethodDef xyzzy_methods[] = {
	{"foo",		xyzzy_foo,	METH_NOARGS,
	 "Return the meaning of everything."},
	{NULL,		NULL}		/* sentinel */
};

static struct PyModuleDef xyzzymodule = {
	{}, /* m_base */
	"xyzzy",  /* m_name */
	0,  /* m_doc */
	0,  /* m_size */
	xyzzy_methods,  /* m_methods */
	0,  /* m_reload */
	0,  /* m_traverse */
	0,  /* m_clear */
	0,  /* m_free */
};

PyObject*
PyInit_xyzzy(void)
{
	return PyModule_Create(&xyzzymodule);
}