Problem with loading .dll

Hi,

I recently encountered a problem when I tried to load external .dll file in Matlab.

 >>loadlibrary('okFrontPanel','okFrontPanelDLL.h')

 Error using loadlibrary

 Building okFrontPanel_thunk_pcwin64 failed.  Compiler output is:

 C:\MATLAB\SupportPackages\R2015b\MW_MinGW_4_9\\bin\gcc -I"D:\Matlab\extern\include" -fexceptions -fno-omit-frame-pointer
-I"D:\Matlab\My Project\win64" -I"D:\Matlab\My Project\win64" "okFrontPanel_thunk_pcwin64.c" -o "okFrontPanel_thunk_pcwin64.dll"
-shared

 In file included from okFrontPanel_thunk_pcwin64.c:27:0:

 D:\Matlab\My Project\win64/okFrontPanelDLL.h:401:94: error: unknown type name 'okEFPGAConfigurationMethod'
 okDLLEXPORT ok_ErrorCode DLL_ENTRY okFrontPanel_GetFPGAResetProfile(okFrontPanel_HANDLE hnd, okEFPGAConfigurationMethod method,
 okTFPGAResetProfile *profile);
                                                                                              ^
 D:\Matlab\My Project\win64/okFrontPanelDLL.h:402:94: error: unknown type name 'okEFPGAConfigurationMethod'

 okDLLEXPORT ok_ErrorCode DLL_ENTRY okFrontPanel_SetFPGAResetProfile(okFrontPanel_HANDLE hnd, okEFPGAConfigurationMethod method,
 const okTFPGAResetProfile *profile);
                                                                                              ^
 okFrontPanel_thunk_pcwin64.c: In function 'ok_ErrorCodeulongokEFPGAConfigurationMethodvoidPtrThunk':

 okFrontPanel_thunk_pcwin64.c:435:2: error: unknown type name 'okEFPGAConfigurationMethod'
  okEFPGAConfigurationMethod p1;
  ^
 okFrontPanel_thunk_pcwin64.c:439:7: error: 'okEFPGAConfigurationMethod' undeclared (first use in this function)

p1=*(okEFPGAConfigurationMethod const *)callstack;
     ^
okFrontPanel_thunk_pcwin64.c:439:7: note: each undeclared identifier is reported only once for each function it appears in
okFrontPanel_thunk_pcwin64.c:439:34: error: expected ')' before 'const'

p1=*(okEFPGAConfigurationMethod const *)callstack;
                                ^
okFrontPanel_thunk_pcwin64.c:439:42: error: expected ';' before 'callstack'

p1=*(okEFPGAConfigurationMethod const *)callstack;
                                        ^
okFrontPanel_thunk_pcwin64.c:443:44: error: expected declaration specifiers or '...' before 'okEFPGAConfigurationMethod'
return ((ok_ErrorCode (*)(unsigned long , okEFPGAConfigurationMethod , void * ))fcn)(p0 , p1 , p2);
                                          ^
okFrontPanel_thunk_pcwin64.c:443:82: error: expected ')' before 'fcn'
return ((ok_ErrorCode (*)(unsigned long , okEFPGAConfigurationMethod , void * ))fcn)(p0 , p1 , p2);

It seems something wrong with "okFrontPanel_thunk_pcwin64", cause I am using Matlab 64-bit version and trying to load a 64-bit library. Could anyone give information about this problem? Thanks a lot.

Answer 1

[Image Analyst]

Search the forum for "thunk" for prior discussions.

[Yimai Peng]

Of course I did this, but still find no answer for this. Now I am working with the 32-bit Matlab. Thanks for your reply.

Answer 2

[spinecho]

(α) In Matlab run

    loadlibrary('okFrontPanel', 'okFrontPanelDLL.h', 'notempdir');

This disables the temp folder thus both the matlab-protofile and the thunk.c file will stay in your working folder. Generates lots of errors too but we can ignore them. So you now have in your working folder the following two files:

okFrontPanel_proto.m

okFrontPanel_thunk_pcwin64.c

(β) Rename okFrontPanel_thunk_pcwin64.c to okFrontPanel_thunk_pcwin64.cpp

(γ) Copy tmwtypes.h from

C:\Program Files\MATLAB\R2014a\extern\include

into your working folder or include path to tmwtypes.h: Additional Include Directories

(δ) Open okFrontPanel_thunk_pcwin64.cpp and change

#include <tmwtypes.h>

to

#include "tmwtypes.h"

Also add

int main(){
            return 0;
                }

(ε) In the command prompt (in my case the Windows SDK Command Prompt) run

cl /EHsc /LD okFrontPanel_thunk_pcwin64.cpp

to create the dll

okFrontPanel_thunk_pcwin64.dll

(στ) In Matlab -> Set Path -> add

C:\Program Files\Opal Kelly\FrontPanelUSB\API-64

(ζ) In Matlab run

loadlibrary('okFrontPanel',@okFrontPanel_proto)

If you interested in the technical details in regard to the thunk and proto files have a look here: On Matlab’s loadlibrary, proto file and pcwin64 thunk