c++ - Export POD-structure from DLL -

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consider following source library.cpp

struct parameter {     const char *path;     int num;     bool flag;     /* , many, many more members... */ };  __declspec(dllexport) void func(const parameter &);

this compiles library library.dll.

as far understand, export declarations export functions , data. since structure parameter doesn't define functions it's not necessary here , omitted it.

but

dumpbin.exe /exports library.dll

reveals, there in fact real difference here: method operator = (const parameter &) exported.

question: there important reasons export parameter, i.e. add __declspec(dllexport) in front of parameter? best practice pod-structures.

normally, pod struct, contain data(that of fundamental types) , no functions, declared in ".h" file given along corresponding .dll.

//mydll.h ------------------------------------------------- #ifndef __mydll_dot_h__ #define __mydll_dot_h__  struct parameter  {     const char *path;     int num;     bool flag; };  #ifdef __dllexport__ __declspec(dllexport) void func(const parameter &); #else __declspec(dllimport) void func(const parameter &); #endif  #endif //#ifndef __mydll_dot_h__ //mydll.h -------------------------------------------------   //client_of_mydll.cpp ------------------------------------- #include "mydll.h"  int main() {     parameter stparameters;     //initialize parameters of stparameters     func(stparameters);  } //client_of_mydll.cpp -------------------------------------

edit: since pod contains purely data, declaration of such pod remains same in dll , client of dll. here purely data means no member functions if pod has struct say, b inside member function b::func(). so, there no important reasons export structure along function.


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