Temporary Files And Directories in Modelica

Our first program will create temporary files and directories. Here’s the full source code:

model TemporaryFilesAndDirectories
  import Modelica.Utilities.Files;
  import Modelica.Utilities.System;
  
  function check
    input Boolean condition;
    input String message;
  algorithm
    assert(condition, message);
  end check;

equation
  when initial() then
    // Create a temporary file
    String tempFileName;
    (tempFileName, _) := Files.createTempFile("sample");
    Modelica.Utilities.Streams.print("Temp file name: " + tempFileName);
    
    // Write some data to the file
    Modelica.Utilities.Streams.writeFile(tempFileName, String({1, 2, 3, 4}));
    
    // Create a temporary directory
    String tempDirName;
    tempDirName := Files.createTempDirectory("sampledir");
    Modelica.Utilities.Streams.print("Temp dir name: " + tempDirName);
    
    // Create a file in the temporary directory
    String filePath;
    filePath := Files.concatenatePaths(tempDirName, "file1");
    Modelica.Utilities.Streams.writeFile(filePath, String({1, 2}));
    
    // Clean up
    Files.remove(tempFileName);
    Files.removeDirectory(tempDirName, true);
  end when;
end TemporaryFilesAndDirectories;

In this Modelica example, we’re using the Modelica.Utilities.Files package to handle file and directory operations. Here’s a breakdown of what the code does:

1. We define a check function that asserts a condition, similar to the error checking in the original example.

2. We use Files.createTempFile to create a temporary file. The function returns the file name.

3. We print the name of the temporary file.

4. We write some data to the file using Modelica.Utilities.Streams.writeFile.

5. We create a temporary directory using Files.createTempDirectory.

6. We print the name of the temporary directory.

7. We create a file inside the temporary directory by concatenating the directory path with a file name using Files.concatenatePaths.

8. Finally, we clean up by removing the temporary file and directory. Note that Files.removeDirectory with the second argument set to true will remove the directory and all its contents.

To run this Modelica model, you would typically use a Modelica simulation environment. The exact commands may vary depending on your specific setup.

Note that Modelica doesn’t have a direct equivalent to Go’s deferred execution, so we’re not able to replicate the defer functionality. Instead, we’re manually calling the cleanup functions at the end of our when initial() block.

Also, Modelica doesn’t have a built-in way to handle raw byte data like Go does. In this example, we’re using String to represent the data we’re writing to files, but in a real application, you might need to use a more appropriate data type or encoding method depending on your specific needs.