use LoadLibrary & GetProcAddress question!
lazarus / 1-Linux

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seewind · 2009-06-03 15:25

the project PyMinMod.lpi on attach file, is use fpc make python extend
module.
there are two methodes to declare python API, like this:
1.function PyInt_FromLong(along : LongInt) : PyObject; cdecl; external
PythonLib;
2.var PyInt_FromLong1: function (along : LongInt) : PyObject; cdecl;
pyhl := LoadLibrary({$ifdef LINUX} '/usr/lib/' + {$endif}PythonLib);
@PyInt_FromLong1 := GetProcAddress(pyhl, 'PyInt_FromLong');

when use PyInt_FromLong1, this module will crack:
see@debian:~/dev/freepascal/demo/simple$ python test.py
An unhandled exception occurred at $B7BB93EE :
EAccessViolation : Access violation
  $B7BB93EE

I have test this code at debian(fpc2.2.4, python2.5) and
ubuntu(fpc2.2.2, python2.6)
other question:
1.on ubuntu, Py_InitModule4 is doesn't work。
@Py_InitModule4 := GetProcAddress(pyhl, 'Py_InitModule4');

2.below two line code is same?
@PyInt_FromLong1 := GetProcAddress(pyhl, 'PyInt_FromLong');
PyInt_FromLong1 := GetProcAddress(pyhl, 'PyInt_FromLong');


please help, thank you!

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icebit · 2009-06-03 17:14

1. Try: Pointer(Py_InitModule4) :=
GetProcAddress(pyhl,'Py_InitModule4');

2. No.

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seewind · 2009-06-04 03:19

Pointer(Py_InitModule4) := GetProcAddress(pyhl,'Py_InitModule4');
the code error:
PyAPI.pas(95,3) Error: Wrong number of parameters specified for call
to "<Procedure Variable>"

have two points to add:
1.the project PyMinMod.lpi run on windows system is fine.
2.other functions like:
  DLL_PyArg_ParseTuple := GetProcAddress(pyhl, 'PyArg_ParseTuple');
  PyCallable_Check := GetProcAddress(pyhl, 'PyCallable_Check');
  PyBool_FromLong := GetProcAddress(pyhl, 'PyBool_FromLong');
have not the issue.

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Leledumbo · 2009-06-04 04:43

In what mode are you compiling? Delphi or ObjFPC?

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seewind · 2009-06-04 07:15

{$MODE Delphi}

This project's code is modify from
http://wiki.lazarus.freepascal.org/Developing_Python_Modules_with_Pasc
al

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Leledumbo · 2009-06-04 07:58

What if you remove the Pointer typecast? And what's the type of:
Py_InitModule4
DLL_PyArg_ParseTuple
PyCallable_Check
PyBool_FromLong