Python mixed programming with C + +

Python calls each other with A/C + + module

Python calls c dynamic-link library
Python's call to C library is simple, packaged into so without any encapsulation, and then using Python's ctypes call.
<test.cpp Generating source files for dynamic libraries >

1. #include <stdio.h>
2. extern "C" {
3. void display () {
4. printf ("This is Display function\n");
5. }
6. }
7. g++ Test.cpp-fpic-shared-o libtest.so

<call.py calling the source file of the dynamic library >

1. Import cTYPES
2. so = cTYPES. Cdll ("./libtest.so")
3. So.display ()

It is important to note that when you use g++ to compile a function or method in a code that generates a dynamic library, you need to use extern "C" to compile

Python calls C + + (with class, overloaded) dynamic-link libraries
But call C + + so is a bit of a hassle, the Internet to find the next, most of the need for extern "C" to assist, that is, can only call C function can not call the method directly but can parse C + + method.
<test.cpp Generating source files for dynamic libraries >

2. #include <Akita/Akita.h>
4. class testlib{
6. Public:
8. void display ();
10. void display (int a);
12. 
    
14. 
    
16. };
18. void TestLib::d isplay () {
20. cout<<"First display"<<endl;
22. }
24. 
    
26. 
    
28. void TestLib::d isplay (int a) {
30. cout<<"Second display"<<endl;
32. }
34. extern "C" {
36. TestLib obj;
38. void display () {
40. Obj.display ();
42. }
44. void Display_int () {
46. Obj.display (2);
48. }
50. }

g++ Test.cpp-fpic-shared-o libtest.so
Using this method is a bit of a hassle but can solve the problem. Notice that there will still be an extern "C" or the built-in dynamic link library does not have the symbolic table of these functions.

<call.py calling the source file of the dynamic library >

1. Import cTYPES
2. so = cTYPES. Cdll ("./libtest.so")
3. So.display ()
4. So.display_int (1)

The results of the operation are as follows:

1. ^[[email Protected]:~/projects/nugget/kvdb-py] #python call.py
2. First display
3. Second Display

C + + Call Python module

<test.cpp >

2. #include <Akita/Akita.h>
4. #include <Python.h>
6. int Main () {
8. Py_initialize ();
10. if (! Py_isinitialized ()) return FALSE;
12. Pyrun_simplestring ("Import sys");
14. Pyrun_simplestring ("sys.path.append ('./')");
16. 
    
18. //import Module
20. pyobject* pmodule = pyimport_importmodule ("Hello");
22. if (!pmodule) {
24. cout<<"Can ' t import module!/n"<<endl;
26. return -1;
28. }
30. 
    
32. pyobject* pdict = pymodule_getdict (pmodule);
34. if (!pdict) {
36. return -1;
38. }
40. 
    
42. //fetch Function
44. pyobject* Pfunhi = pydict_getitemstring (pdict, "display");
46. Pyobject_callfunction (Pfunhi, "s", "Crazybaby");
48. Py_decref (PFUNHI);
50. 
    
52. //release
54. Py_decref (Pmodule);
56. Py_finalize ();
58. return 0;
60. }

#g + + test.cpp-i/usr/local/include/python2.7-ldl-lutil-lpthread-lpython2.7

<call.py>

1. def Display (name):
2. Print "HI", name

———

C + + writes extension modules for Python
Python provides scripting interfaces for C + +.

The interaction between the two is very convenient.

From:blog.csdn.net/crazyjixiang Crazyjixiang

Python mixed programming with C + +