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Please be patient, its been several years since I've done anything C\C++ and I am trying to 're-learn'.

How do I get a "string" from a C DLL?

This is the C code I am using to start with (VC++ 6)

Code:
#include "stdafx.h"

#include <stdio.h>

#include <time.h>

BOOL APIENTRY DllMain( HANDLE hModule, 

                       DWORD  ul_reason_for_call, 

                       LPVOID lpReserved

                     )

{

    return TRUE;

}

int ReportVersion() {

    return 1;

    }

char *GetDateTime(){

    time_t rawtime;

    time ( &rawtime );

    return ctime (&rawtime);

}

I have a def file with my functions.

This is how I am calling the functions in FB.

Code:
'$inclib: "testdll01.dll"

declare function rVersion cdecl alias "ReportVersion" () as integer

declare function Now cdecl alias "GetDateTime" () as string ptr

? rVersion

? now

sleep

If I don't use the String Ptr (and use only String) in the Now function it crashes. But with the pointer, I get the address (obvious), when what I want is the content.

Am I way off base with this?

The return type must be "byte ptr", "string" is a struct in FB.

To copy the returned string to an FB string simply do: s = *mybyteptrfunc() -- "s" can be a fixed-len or var-len string.

Thanks! That works perfectly.

Code:
'$inclib: "testdll01.dll"

declare function rVersion cdecl alias "ReportVersion" () as integer

declare function tGetDateTime cdecl alias "GetDateTime" () as byte ptr

function Now () as string

   Now = *tGetDateTime()

end function

dim s as string

? rVersion

? now

sleep

keeling

v3cz0r

keeling