Thank you for reaching out and detailing the process you've followed so far in exporting your Simulink model to a standalone FMU with source code for cross-platform use. Based on your description, it appears that the issue you're encountering with STAR CCM+ not being able to find the `.xml` file may stem from how the FMU was repackaged after inserting the compiled `.so` file for Linux.
Repackaging an FMU requires careful attention to ensure that the file structure within the FMU (which is essentially a ZIP file) is preserved according to the FMI standard. Here's a step-by-step guide to ensure the FMU is repackaged correctly:
1. Correct Directory Structure
First, it's crucial to maintain the correct directory structure inside the FMU. The `modelDescription.xml` file must be at the root level of the FMU, and the `.so` file should be placed in the `binaries/linux64` directory, as you've done. This structure is essential for the FMU to be recognized correctly by simulation tools.
2. Repackaging the FMU
To correctly repackage the FMU, follow these steps:
Step 1: Navigate to the root directory where you've extracted the FMU contents. This directory should directly contain the `modelDescription.xml` file and the `binaries/`, `documentation/`, `sources/`, and any other directories.
Step 2: Use the `zip` command to create the FMU file, ensuring you're zipping the contents of the directory and not the directory itself. Run the following command from within the root directory of your FMU contents:
zip -r -0 ../my_model.fmu *
This command creates the FMU file named `my_model.fmu` one directory level up from your current location, ensuring that the structure is preserved as required.
Important Note: Do not zip the folder that contains the FMU contents; zip the contents directly. This ensures that when the FMU is unzipped by STAR CCM+ or any other tool, the `modelDescription.xml` file and other necessary directories are immediately accessible at the root level of the archive.
3. Verify the FMU Structure
After repackaging, you can verify the structure of the FMU by listing its contents with:
Ensure that the `modelDescription.xml` file is listed at the root and that the directory structure matches what is expected.
4. Testing the Repackaged FMU
Once repackaged, try loading the FMU in STAR CCM+ again. If the issue persists, double-check the FMU's directory structure and ensure that no steps were missed during the repackaging process.
By following these steps, you should be able to repackage your FMU correctly for cross-platform use, ensuring that simulation tools like STAR CCM+ can properly read and execute the FMU without encountering errors about missing files.
If you have any further questions or encounter additional issues, feel free to reach out.
I hope this helps.
