How to create a linux shared object from matlab code (Matlab 2015b)

Hello everyone,

I want to connect matlab written functions into our vehicle control unit. The control unit is a myRio 1900 which gets programmed with Labview. Until now I managed to create .dll files from my function by using the matlab coder. I could use the .dll running the labview code on windows.

But for now I am missing the last step as the myRio is running under Ni Realtime linux I cant use the .dll file anymore. I would need a linux shared object. Therefore I want to ask if and how I can create the .so file from matlab. It would be really benificial for the application if there werent to many steps involved as the process will get repeated quite frequently.

I found this question which exlained it for some older version but couldnt replicate the result. Apperently the usage of mcc has changed.

Currently I am using: Win 7 64bit Profesional, Matlab 2015b 32bit formula Student Licence (is there a way to create 32bit dlls from a 64bit Matlab?)

I appreciate any help!

Best Regards, Stephan

Answer 1

[Christoph Hahn]

Dear Stephan,

regarding your first question, I have a twofold answer:

1. Use a cross-compiling workflow such that one Cross-compiling on Windows for Linux
2. MATLAB is also available on Linux OS: MathWorks Platform Availability . If that is a suitable workflow, you can do everything in Linux.

Concerning your question about 32/64bit compatiblity again there are two options:

1. Stick to your workflow of using MATLAB 32bit
2. Alternatively, ou need to create custom toolchain which allows you to call the 32-bit version of the Microsoft Visual Studio Compiler.

The workflow for the 2nd option is as follows:

Please execute the "generate_32_bit_dll" function to create the custom toolchain which generates 32 bit DLL using ert_shrlib.TLC and choose 'Microsoft 64-bit compiler targeting 32-bit DLL | nmake makefile (64-bit Windows)' for the toolchain in the model's Configuration Parameters > Code Generation pane. How can I build a 32-bit shared library (DLL) with Embedded Coder on Windows 64-bit MATLAB? Answer You need to create custom toolchain which allows you to call the 32-bit version of the Microsoft Visual Studio Compiler.

Please execute the "generate_32_bit_dll" function to create the custom toolchain which generates 32 bit DLL using ert_shrlib.TLC and choose 'Microsoft 64-bit compiler targeting 32-bit DLL | nmake makefile (64-bit Windows)' for the toolchain in the model's Configuration Parameters > Code Generation pane.

Let me know whether these answers are helpful to you!

Cheers, Christoph

[Walter Roberson]

Note: the 32 bit executables that Christoph describes are Windows 32 bit executables. If the requirement is to generate 32 bit Linux executables then you need to go through a cross-compiling setup. Also, MATLAB is no longer available to run on 32 bit Linux natively.

[Stephan Heidrich]

Hello Christoph and Walter,

thank you both for your help and directing.

First I was trying to use matlab 2012a 32bit coder installed on a linux which got me a .so file. Unfortunately it didnt work with our rt system (eventhough I was setting it to ARM Cortex A).

The second approach with the cross compiling was bringing the right results. In cooperation with Ni I was using the two following tutorials to create the .so from the matlab exported c files:

preadjusted Eclipse Enviroment

Tutorial how to (unfortunately in German)

Answer 2

[Walter Roberson]

It is not that mcc has changed (though it has) but rather that you are trying to "cross-compile", creating a Linux library from MS Windows. MATLAB Coder should be able to do that if you configure the correct toolchain; unfortunately I do not know what the correct toolchain is (especially not for a realtime Linux.)

For example, MATLAB Coder is invoked by Simulink to build models for deployment on Arduino, which uses Linux, so it must be possible to configure. I have not had reason to do that myself (I do not have any Linux hardware.)