C#

using System.IO;
using System.Runtime.InteropServices;
using System.Text;
 
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
private static extern int GetShortPathName(
    [MarshalAs(UnmanagedType.LPTStr)]
    string path,
    [MarshalAs(UnmanagedType.LPTStr)]
    StringBuilder shortPath,
    int shortPathLength);
 
public static string GetShortPathName(string fileName)
{
    if (fileName == null || fileName.Length == 0) 
        return string.Empty;
    
    if (!Path.IsPathRooted(fileName)) 
        fileName = Path.GetFullPath(fileName);
    
    try 
    {
        int len = GetShortPathName(fileName, null, 0);
        if (len > 0) 
        {
            StringBuilder sb = new StringBuilder(len);
            GetShortPathName(fileName, sb, len);
            return sb.ToString();
        }
        else
            return fileName;
    }
    catch 
    {
        return fileName;
    }
}

You see the Standards change. - Fellow co-worker