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Author: janvorli

src/coreclr/nativeaot/System.Private.CoreLib/src/System/RuntimeExceptionHelpers.cs

@@ -221,7 +221,7 @@ internal static unsafe void FailFast(string? message, Exception? exception, RhFa
                     string outputMessage;
                     if (exception != null)
                     {
-                        prefix = "Unhandled Exception: ";
+                        prefix = "Unhandled exception. ";
                         outputMessage = exception.ToString();
                     }
                     else

src/tests/baseservices/exceptions/unhandled/unhandled.cs

@@ -24,7 +24,6 @@ static int Main(string[] args)
 
             testProcess.StartInfo.FileName = Environment.ProcessPath;
             testProcess.StartInfo.Arguments = Environment.CommandLine + " throw";
-            testProcess.StartInfo.UseShellExecute = false;
             testProcess.StartInfo.RedirectStandardError = true;
             testProcess.ErrorDataReceived += (sender, line) => 
             {
@@ -41,7 +40,7 @@ static int Main(string[] args)
             testProcess.CancelErrorRead();
 
             int expectedExitCode;
-            if ((Environment.OSVersion.Platform == PlatformID.Unix) || (Environment.OSVersion.Platform == PlatformID.MacOSX))
+            if (!OperatingSystem.IsWindows())
             {
                 expectedExitCode = 128 + 6;
             }
@@ -60,7 +59,7 @@ static int Main(string[] args)
                 return 101;
             }
 
-            if (Regex.Match(lines[0], @"Unhandled exception[.:] System\.Exception\: Test", RegexOptions.IgnoreCase) == Match.Empty)
+            if (lines[0] != "Unhandled exception. System.Exception: Test")
             {
                 Console.WriteLine("Missing Unhandled exception header");
                 return 102;