Mailman 3 January 2010 - Cplusplus-sig

boost::python embedding error - runtime - Mac OS X - 1.38
by Igor Karpov Oct. 1, 2014

Oct. 1, 2014

Hi, I am trying to run the following program: #include <iostream> #include <Python.h> #include <boost/python.hpp> using namespace boost::python; using namespace std; int main(int argc, char** argv) { { // Using Python/C Py_Initialize(); PyObject* main_module = PyImport_ImportModule("__main__"); PyObject* globals = PyEval_GetGlobals(); PyObject* locals = PyEval_GetLocals(); PyRun_SimpleString("print 'Hello World, from Python/C!'\n"); Py_Finalize(); } { // Using boost::python Py_Initialize(); object main_module = import("__main__"); object main_namespace = main_module.attr("__dict__"); try { object ignored = exec("print 'Hello World, from boost::python!'\n", main_namespace); Py_Finalize(); } catch (error_already_set const& e) { PyErr_Print(); return 1; } } return 0; } on Linux (both x86 and x86_64), with Ubuntu's default version of Boost (1.34.1) installed, I am able to do so as expected: $ ./embed Hello World, from Python/C! Hello World, from boost::python! on Mac OS X, I get a runtime error: $ ./embed Hello World, from Python/C! Bus Error Running with gdb, this is the stack trace: Hello World, from Python/C! Program received signal EXC_BAD_ACCESS, Could not access memory. Reason: KERN_PROTECTION_FAILURE at address: 0x00000000 0x00000000 in ?? () (gdb) where #0 0x00000000 in ?? () #1 0x00bb618f in PyEval_GetGlobals () #2 0x00bce0dd in PyImport_Import () #3 0x00bce2b0 in PyImport_ImportModule () #4 0x008127d4 in boost::python::import (name=@0xbffff4a8) at libs/python/src/import.cpp:20 #5 0x00004446 in main (argc=1, argv=0xbffff510) at embed.cc:22 For this Mac, boost version is latest (1.38) and python version is: Python 2.5.4 (r254:67917, Dec 23 2008, 14:57:27) [GCC 4.0.1 (Apple Computer, Inc. build 5363)] on darwin Is this a bug? I attached the source and the cmake file I am using to build, for convenience. Thanks, --Igor.

4 6

CMake and getting starting with boost.python
by Braddock Gaskill Aug. 5, 2011

Aug. 5, 2011

Yesterday I became a boost.python user, after years of heavy SWIG usage. I would have started using boost.python years ago except for the bjam learning curve. I spent hours TRYING on multiple occasions, but got lost every time trying to get the page one example to build with bjam. Here is how to build the "greet" example with a four line CMake file: cat >>CMakeLists.txt <<EOF LINK_LIBRARIES(boost_python) INCLUDE_DIRECTORIES("/usr/include/python2.5") LINK_DIRECTORIES("/usr/lib/python2.5") # Not needed? ADD_LIBRARY(hello SHARED hello.cpp) EOF You WILL have to `mv libhello.so hello.so` after building. Works for me under Ubuntu Linux 6.10 after apt-get install cmake python2.5-dev boost-python-dev cmake make mv libhello.so hello.so ipython In [1]: import hello In [2]: hello.greet() Out[2]: 'hello, world' Boost.Python has been a joy to learn and use since I got past bjam. I had a moderately large API wrapped in just my first couple hours of learning (less time than I spent messing with bjam). Any additional advice for using CMake to build boost.python? Braddock Gaskill

4 4

How to import a boost::python dll in windows?
by ichijoji Aug. 5, 2011

Aug. 5, 2011

I'm trying to port some research code that uses boost::python to expose a library to python to windows, but I'm having trouble importing the dll into python. I'm compiling using msvc 2005 and using python 2.5, but when I try to import the module I get this: Traceback (most recent call last): File "main.py", line 1, in <module> import object File "c:\code\sge\code\scripts\object.py", line 1, in <module> import sge ImportError: No module named sge My module is named sge and I'm compiling to sge.dll. Is there some obvious reason why python wouldn't be able to find my dll? When I compile on linux into an so this code works fine. -- View this message in context: http://www.nabble.com/How-to-import-a-boost%3A%3Apython-dll-in-windows--tf3… Sent from the Python - c++-sig mailing list archive at Nabble.com.

4 4

Getting object for PyObject (reference counting)
by Murray Cumming Feb. 11, 2010

Feb. 11, 2010

I can't find any definitive documentation that tells me how I should get a boost::python::object to wrap an existing PyObject*. I guess that there's a way to do it that uses an existing reference, and a way that takes an extra reference. -- murrayc(a)murrayc.com www.murrayc.com www.openismus.com

5 10

Using code generated by Py++ as a Python extension
by Chris Lasher Jan. 31, 2010

Jan. 31, 2010

I asked this question on Stack Overflow, but realized that perhaps few from the Py++ community are there yet. I'm re-posting the question here; I hope you don't mind. http://stackoverflow.com/questions/2169948/using-code-generated-by-py-as-a-… I have a need to wrap an existing C++ library for use in Python. After reading through this answer http://stackoverflow.com/questions/456884/extending-python-to-swig-or-not-t… choosing an appropriate method to wrap C++ for use in Python, I decided to go with Py++. I walked through the tutorial for Py++ http://www.language-binding.net/pyplusplus/documentation/tutorials/module_b…, using the tutorial files, and I got the expected output in generated.cpp, but I haven't figured out what to do in order to actually use the generated code as an extension I can import in Python. I'm sure I have to compile the code, now, but with what? Am I supposed to use bjam? Thanks, Chris

2 1

FW: Boost.Python.function bug
by Matthew Scouten (TT) Jan. 29, 2010

Jan. 29, 2010

Hey folks, One of my users spotted this, and I think it is an error in BP. It works the same for any function exported. He states it more completely then I could, So I will just forward what he sent to me: From: Ben Walker (TT) Sent: Friday, January 29, 2010 3:27 PM To: Matthew Scouten (TT) Subject: Boost.Python.function bug >>> boost_func <Boost.Python.function object at 0x011A0228> >>> type(boost_func) <type 'Boost.Python.function'> >>> import types >>> isinstance(boost_func, types.BuiltinFunctionType) True >>> dir(boost_func) ['__call__', '__class__', '__cmp__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__module__', '__name__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__self__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__'] >>> boost_func.__self__ Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'Boost.Python.function' object has no attribute '__self__' >>> hasattr(boost_func, '__self__') False >>> dir() says Boost.Python.function objects have a __self__ member, but accessing it throws an AttributeError. Furthermore, real builtin functions have a __self__ member and some python libraries assume that if something is an instance of a builtin function, it will have a __self__ member. Testing via hasattr does function appropriately for the actual behavior. This was discovered while trying to use Sphinx's autodoc extension (sphinx.pocoo.org) on a C++ library wrapped via Boost.Python.

1 0

Re: [C++-sig] boost python calling conventions support patch submission (__stdcall, __cdecl, __fastcall)
by David Abrahams Jan. 28, 2010

Jan. 28, 2010

At Wed, 27 Jan 2010 12:17:07 +0100, Nicolas Lelong wrote: > > My thought was to leave the library files as-is, and to simply enable > the unit tests on 'toolsets' related to Microsoft compilers, and perhaps > add later other compilers that might support these calling conventions, > based on users needs. > > This way, each user would be free to configure its boost.python > without hassle, and tests would not break on 'uncertified' toolsets. I'm not sure exactly what "enable the unit tests" means in this case. Can you be explicit and/or preferably provide an illustrative patch? -- Dave Abrahams Meet me at BoostCon: http://www.boostcon.com BoostPro Computing http://www.boostpro.com

2 1

Problem running the quickstart
by Daniel Lidström Jan. 27, 2010

Jan. 27, 2010

Hi, I have troubles compiling and running the quickstart: C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\example\quickstart>bjam toolset=msvc-9.0 --verbose-test test --debug -configuration notice: found boost-build.jam at C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\example\quickstart\boost-build.jam notice: loading Boost.Build from C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\example\quickstart\..\..\..\..\tool s\build\v2 notice: Searching C:\Windows U:\ C:\cygwin\home\daniel C:\Users\Daniel.SBG C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\ python\example\quickstart\../../../../tools/build/v2 C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/kernel C:/Us ers/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/util C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/build C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/tools C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v 2/contrib C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/. for site-config configuration file site-config.jam . notice: Loading site-config configuration file site-config.jam from C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\ example\quickstart\..\..\..\..\tools\build\v2\site-config.jam . notice: Searching U:\ C:\cygwin\home\daniel C:\Users\Daniel.SBG C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\exam ple\quickstart\../../../../tools/build/v2 C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/kernel C:/Users/Daniel. SBG/Programming/boost_1_41_0/tools/build/v2/util C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/build C:/Users/D aniel.SBG/Programming/boost_1_41_0/tools/build/v2/tools C:/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/contrib C :/Users/Daniel.SBG/Programming/boost_1_41_0/tools/build/v2/. for user-config configuration file user-config.jam . notice: Loading user-config configuration file user-config.jam from C:\Users\Daniel.SBG\Programming\boost_1_41_0\libs\python\ example\quickstart\..\..\..\..\tools\build\v2\user-config.jam . notice: Searching ../../../.. for project-config configuration file project-config.jam . notice: Loading project-config configuration file project-config.jam from ..\..\..\..\project-config.jam . notice: [msvc-cfg] msvc-9.0 detected, command: 'c:\Program Files\Microsoft Visual Studio 9.0\VC\bin\cl.exe' notice: [msvc-cfg] msvc-8.0 detected, command: 'C:\Program Files\Microsoft Visual Studio 8\VC\bin\cl.exe' notice: will use 'c:\Program Files\Microsoft Visual Studio 9.0\VC\bin\cl.exe' for msvc, condition <toolset>msvc-9.0 notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>/<address-model>', setup: 'call "c:\Program Files\Microsoft Vi sual Studio 9.0\VC\vcvarsall.bat" x86 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>/<address-model>32', setup: 'call "c:\Program Files\Microsoft Visual Studio 9.0\VC\vcvarsall.bat" x86 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>x86/<address-model>', setup: 'call "c:\Program Files\Microsoft Visual Studio 9.0\VC\vcvarsall.bat" x86 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>x86/<address-model>32', setup: 'call "c:\Program Files\Microso ft Visual Studio 9.0\VC\vcvarsall.bat" x86 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>/<address-model>64', setup: 'call "c:\Program Files\Microsoft Visual Studio 9.0\VC\vcvarsall.bat" x86_amd64 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>x86/<address-model>64', setup: 'call "c:\Program Files\Microso ft Visual Studio 9.0\VC\vcvarsall.bat" x86_amd64 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>ia64/<address-model>', setup: 'call "c:\Program Files\Microsof t Visual Studio 9.0\VC\vcvarsall.bat" x86_ia64 >nul ' notice: [msvc-cfg] condition: '<toolset>msvc-9.0/<architecture>ia64/<address-model>64', setup: 'call "c:\Program Files\Micros oft Visual Studio 9.0\VC\vcvarsall.bat" x86_ia64 >nul ' notice: [cmdline-cfg] Detected command-line request for msvc-9.0: toolset= msvc version= 9.0 notice: [cmdline-cfg] toolset msvc-9.0 already configured notice: iostreams: not using zlib compression notice: iostreams: not using zlib compression notice: iostreams: not using bzip2 compression notice: iostreams: not using bzip2 compression notice: [python-cfg] Configuring python... notice: [python-cfg] Registry indicates Python 3.0 installed at "C:\Python30\" notice: [python-cfg] Checking interpreter command "python"... notice: [python-cfg] running command 'DIR /-C /A:S "C:\Python30\python.exe" 2>&1' notice: [python-cfg] running command 'python -c "from sys import *; print('version=%d.%d\nplatform=%s\nprefix=%s\nexec_prefix =%s\nexecutable=%s' % (version_info[0],version_info[1],platform,prefix,exec_prefix,executable))" 2>&1' notice: [python-cfg] ...requested configuration matched! notice: [python-cfg] Details of this Python configuration: notice: [python-cfg] interpreter command: "python" notice: [python-cfg] include path: "C:\Python30\Include" notice: [python-cfg] library path: "C:\Python30\libs" notice: [python-cfg] DLL search path: "C:\Python30" error: Unable to find file or target named error: 'test_extending.py' error: referred from project at error: '.' There does not seem to be a script by the name test_extending.py. Did I miss something? Thanks in advance! Regards, Daniel Lidström Stockholm, Sweden

2 4

wrapping vector of pointers
by martin manduch Jan. 26, 2010

Jan. 26, 2010

Hi, I need to wrap vector of pointers, because it's parameter in one function... I have following code: struct X { X(int nn) {n=nn;} int n; }; BOOST_PYTHON_MODULE(myVector) { class_<X>("X", init<int>()) .def_readwrite("n", &X::n); class_<std::vector<X*> >("XVec") .def(vector_indexing_suite<std::vector<X*> >()) ; } I want to make XVec responsible for memory, which is addressed through pointers, but I don't know how. >>vec=XVec() >>a=X(7) >>vec.append(a) >>del a >>vec[0].n It prints 1682309121, but I want it to print: 7 Martin

2 1

Please help: boost python 1.41 extension problem
by lin yun Jan. 26, 2010

Jan. 26, 2010

Hi, I am trying to install boost 1.41 on Redhat Enterprise Linux 5.3 and I got problem with the extension test. Following the instructions here: http://www.boost.org/doc/libs/1_41_0/libs/python/doc/building.html - I built boost python using bjam. - cd into the libs/python/example/quickstart/ directory - bjam toolset=gcc --verbose-test test Now I see embedding test passes while extension test failed. I got the same problem with boost 1.35, 1.37 on Fedora 7. Below is the error messages: ../../../../boost/type_traits/detail/cv_traits_impl.hpp:37: internal compiler error: in make_rtl_for_nonlocal_decl, at cp/decl.c:5067 Please submit a full bug report, with preprocessed source if appropriate. See <URL:http://bugzilla.redhat.com/bugzilla> for instructions. Preprocessed source stored into /tmp/ccIhs3ut.out file, please attach this to your bugreport. "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -fPIC -I"../../../.." -I"/usr/include/python2.4" -c -o "bin/gcc-4.1.2/debug/extending.o" "extending.cpp" ...failed gcc.compile.c++ bin/gcc-4.1.2/debug/extending.o... ...skipped <pbin/gcc-4.1.2/debug>extending.so for lack of <pbin/gcc-4.1.2/debug>extending.o... ...skipped <pbin/test_ext.test/gcc-4.1.2/debug>test_ext for lack of <pbin/gcc-4.1.2/debug>extending.so... Does anyone encounter the same issue as me ? Anyone can help ? Thanks a lot, Yun

2 4