Re: RE: "undefined reference" error message when using mkoctfile to create oct file

[Tatsuro MATSUOKA]

----- Original Message -----

> From: Yan Zhang 
> To: "help-octave
> Cc: 
> Date: 2017/2/22, Wed 07:21
> Subject: RE: RE: "undefined reference" error message when using mkoctfile to 
> create oct file
> 
> I tried the "-L." flag but got the same message:
> 
> ---------------------------------------------
>>>  mkoctfile PowerMeter.cc -L. -lusbdll
> ./usbdll.lib: error adding symbols: File in wrong format
> collect2.exe: error: ld returned 1 exit status
> warning: mkoctfile exited with failure status
> warning: called from
>     mkoctfile at line 171 column 5
> ---------------------------------------------
> 
>> I guess the "lib" file I created using Visual Studio 2015 is not 
> recognized by mkoctfile.


Sorry my confusion.

You probably made library file using MS Visual Studio related tool.
However, octave for window uses MinGW w64 GCC.

I have experienced to make library file for GCC from windows dll libraries.
I used  pexports and dlltool on MinGW.


***********************************
Tool preparation

dlltool is fortunately shipped with octave distribution but pexports is not 
shiped.
Therefore pexports should be downloaded.

https://sourceforge.net/projects/mingw/files/MinGW/Extension/pexports/pexports-0.47/pexports-0.47-mingw32-bin.tar.xz/download


The binary archivied in tar.xz
pexports-0.47-mingw32-bin.tar.xz


Therefore you need un-archive software which can handle tar.xz.
I use 7-zip application which can download from
http://www.7-zip.org/


extract pexport.exe (is located in bin folder in archived file)
copy it to the folder where target dll file is located or 
octave bin folder (typical location C:\octave\Octave-4.0.0\bin)
***********************************


***********************************
make library file for dll

* Start octave

* Octave prompt
>> cd <path to the folder where dll file located>
>> system bash

The you see the bash prompt
bash-3.1$

On bash prompt (please change xxx to your situation)
bash-3.1$  pexports xxx.dll > libxxx.def

bash-3.1$  dlltool -D xxx.dll -d libxxx.def -l libxxx.dll.a

Useally library file lib(name).dll.a is used for MinGW environments.

***********************************

Note that the above from my experience.
It is possible that you will not get successful result.

Tatsuro