About Python's C API

[Link]

Jeff,

First, I need to say you are so smart.
I really appreciated your help that of course good idea to solve about my
extraction's prblem.

Following your advise, i obtained  the value of variable from Python in
developing C/API.

By the way, if I had added the statement  "Py_DECREF(m); m = NULL;",
It would be crash during running program.
So that need to remove this statement.

Shall I ask you any problem if no this statment at here?
Any trouble will be happened?

With best regards.
Link

"Jeff Epler" <jepler at unpythonic.net>
???????:mailman.1063850265.9616.python-list at python.org...
> Let me start by saying I'm not a pro with the C API of Python.
>
> With PyRun_SimpleString(), everything takes place in the special
> __main__ module:
>     PyRun_SimpleStringFlags(const char *command, PyCompilerFlags *flags)
>     {
>     PyObject *m, *d, *v;
>     m = PyImport_AddModule("__main__");
>     if (m == NULL)
>     return -1;
>     d = PyModule_GetDict(m);
>     v = PyRun_StringFlags(command, Py_file_input, d, d, flags);
>     if (v == NULL) {
>     PyErr_Print();
>     return -1;
>     }
>     Py_DECREF(v);
>     if (Py_FlushLine())
>     PyErr_Clear();
>     return 0;
>     }
>
> So, to get the attribute x from __main__, convert it to a string, and
> printf() it, you'd use this sequence [all untested]:
>     PyObject *m, *d, *x, *s;
>
>     /* m is a "new" reference */
>     m = PyImport_AddModule("__main__");
>     if (m == NULL)
>     return -1;
>     /* d is a "borrowed" reference */
>     d = PyModule_GetDict(m);
>     Py_DECREF(m); m = NULL; /* Done with m -- decref and set to NULL */
>     x = PyDict_GetItemString(d, "x")
>     /* x is a "borrowed" reference */
>     if (x == NULL) {
> PyErr_Print();
> return;
>     }
>     /* s is a "new" reference */
>     s = PyObject_Str(x);
>     if (s == NULL) {
> PyErr_Print();
> return;
>     }
>     printf("x: %s\n", PyString_AsString(s));
>     Py_DECREF(s); s = NULL; /* Done with s -- decref and set to NULL */
>
> If you're programming in C++, you might benefit from checking out
boost.python at
>     http://boost.org/libs/python/doc/index.html
> I'm not actually a boost.python user, but I've heard good things about it.
>
> Jeff
>