Hi all.
I have a class with virtual functions.
This class lives in DLL. In main program I use this class by obtaining
his pointer (by function that's exports from dll).

class CfromDLL
{
...
virtual int Foo();
...
};

CfromDLL* GetAPI();

I want use a std::auto_ptr (std::auto_ptr<CfromDLL> pnt) on this class.
And I get the linkers errors.
But if I use an explicit pointer (CfromDLL *pnt) - it's all right.
Why I have the linkers crash with auto_ptr ?

PS. Don't tell me about FAQ, because I can't go in Interet now.

Marchello wrote:[color=blue]
> Hi all.
> [redacted]
>
> PS. Don't tell me about FAQ, because I can't go in Interet now.
>[/color]

DLLs are beyond the scope of the Standard. And I will tell you about
the FAQ, because the only way to post to this group is to be on the Net.

Hint. The Internet is not just the web.

> DLLs are beyond the scope of the Standard.

But I did not ask anything about DLL.
[color=blue]
> And I will tell you about the FAQ, because the only way to post to this
> group is to be on the Net.[/color]

No. It is no one way.
We have a several servers that's provides me to the news groups
and to the Net separately.
I can write here, but I can't see any web-pages.
[color=blue]
> Hint. The Internet is not just the web.[/color]
I know.

Hi

Marchello wrote:
[color=blue]
> Hi all.
> I have a class with virtual functions.
> This class lives in DLL. In main program I use this class by obtaining
> his pointer (by function that's exports from dll).[/color]

(Elsewhere in the thread you say you haven't asked about dlls. Then why do
you mention them at all, if you know your problem has nothing to do with
dlls?)
[color=blue]
> class CfromDLL
> {
> ..
> virtual int Foo();
> ..
> };
>
> CfromDLL* GetAPI();
>
> I want use a std::auto_ptr (std::auto_ptr<CfromDLL> pnt) on this class.
> And I get the linkers errors.[/color]

What errors?
I'm sorry, the dust layer on my crystal ball is too thick...
[color=blue]
> Why I have the linkers crash with auto_ptr ?[/color]

It doesn't really crash, right?
Because otherwise you should really ask your compiler vendor...

Markus

Marchello wrote:[color=blue]
> Hi all.
> I have a class with virtual functions.
> This class lives in DLL. In main program I use this class by obtaining
> his pointer (by function that's exports from dll).
>
> class CfromDLL
> {
> ..
> virtual int Foo();
> ..
> };
>
> CfromDLL* GetAPI();
>
> I want use a std::auto_ptr (std::auto_ptr<CfromDLL> pnt) on this class.
> And I get the linkers errors.
> But if I use an explicit pointer (CfromDLL *pnt) - it's all right.
> Why I have the linkers crash with auto_ptr ?
>
> PS. Don't tell me about FAQ, because I can't go in Interet now.[/color]

Please post the linker error you're getting.

> Please post the linker error you're getting.

One of the errors:
error LNK2001: unresolved external symbol "public: virtual int __stdcall
CSound::IsStop(void)" (?IsStop@CSound@@UAGHXZ)

(CSound - is my class with virtual functions)

The errors occurs when I add declaration: std::auto_ptr<CSound> S;

"Marchello" <marchello@rtf-15.ntu-kpi.kiev.ua> wrote in message
news:doo7qp$471$1@news.ntu-kpi.kiev.ua...[color=blue][color=green]
>> Please post the linker error you're getting.[/color]
>
> One of the errors:
> error LNK2001: unresolved external symbol "public: virtual int __stdcall
> CSound::IsStop(void)" (?IsStop@CSound@@UAGHXZ)
>
> (CSound - is my class with virtual functions)
>
> The errors occurs when I add declaration: std::auto_ptr<CSound> S;[/color]
You should make sure that CSound class is exported by DLL code and imported
by EXE code.
Like this:
// file: Sound.h
....
#ifdef MY_DLL
#define MY_EXPORT_IMPORT __declspec(dllexport)
#else
#define MY_EXPORT_IMPORT __declspec(dllimport)
#endif
class MY_EXPORT_IMPORT CSound
{
public:
...
virtual int __stdcall IsStop();
...
};

In preprocessor settings for the DLL you should declare:
MY_DLL=1

In preprocessor settings for the EXE don't declare MY_DLL symbol at all.

Boris

> You should make sure that CSound class is exported by DLL code and[color=blue]
> imported by EXE code.
> Like this:
> // file: Sound.h
> #ifdef MY_DLL
> #define MY_EXPORT_IMPORT __declspec(dllexport)
> #else
> #define MY_EXPORT_IMPORT __declspec(dllimport)
> #endif
> class MY_EXPORT_IMPORT CSound
> {
> public:
> ...
> virtual int __stdcall IsStop();
> ...
> };[/color]

Yes, I know it.
But I am doing this by the another way.

I include the sound.lib to my project by:
#pragma comment (lib, "sound.lib")

And use the import function to create the CSound object:
#define SND_API extern "C" __declspec (dllimport)
SND_API CSound* CreateSoundAPI();

If I write the next:
CSound *Sound;
Sound = CreateSoundAPI(); - it's all right.
But if I write:
std::auto_ptr<CSound> Sound; - I have the linker's errors.

Marchello wrote:[color=blue]
> I include the sound.lib to my project by:
> #pragma comment (lib, "sound.lib")
>
> And use the import function to create the CSound object:
> #define SND_API extern "C" __declspec (dllimport)
> SND_API CSound* CreateSoundAPI();
>
> If I write the next:
> CSound *Sound;
> Sound = CreateSoundAPI(); - it's all right.
> But if I write:
> std::auto_ptr<CSound> Sound; - I have the linker's errors.
>[/color]

std::auto_ptr calls CSound's destructor. Do you have the destructor and
and all functions it calls (like IsStop) defined?

Martin.