python dll return value is wrong -

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i have made dll contains code:

#pragma once  extern double __declspec(dllexport) add(double a, double b); extern double __declspec(dllexport) dif(double a, double b);  #include "testdll.h"  double add(double a, double b) {     return + b; }  double dif(double a, double b) {     return - b; }

the python code calls add function:

    = ctypes.c_double(1);     b = ctypes.c_double(2);     mydll = ctypes.cdll('testdll.dll');     mydll.restype = ctypes.c_double;     ret  = mydll.addnumbers(a, b);

the problem add function doesnt return a+b screwd value: 2619340

please help

the return type double, should set restype so:

hlldll.add.restype = ctypes.c_double hlldll.add.argtypes = [ctypes.c_double, ctypes.c_double]

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