[dotnet-trace] Improve supported platform messages for musl.

src/Tools/Common/Commands/Utils.cs

@@ -2,8 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using System.Diagnostics;
 using System.Collections.Generic;
+using System.Diagnostics;
 using Microsoft.Diagnostics.NETCore.Client;
 using Microsoft.Diagnostics.Tools.Common;
 

src/Tools/dotnet-trace/CommandLine/Commands/CollectLinuxCommand.cs

@@ -41,15 +41,33 @@ public CollectLinuxCommandHandler(IConsole console = null)
             rewriter = new LineRewriter(Console);
         }
 
+        internal static bool IsSupported()
+        {
+            bool isSupportedLinuxPlatform = false;
+            if (OperatingSystem.IsLinux())
+            {
+                isSupportedLinuxPlatform = true;
+                try
+                {
+                    string ostype = File.ReadAllText("/etc/os-release");
+                    isSupportedLinuxPlatform = !ostype.Contains("ID=alpine");
+                }
+                catch (Exception ex) when (ex is FileNotFoundException or DirectoryNotFoundException or IOException) {}
+            }
+
+            return isSupportedLinuxPlatform;
+        }
+
         /// <summary>
         /// Collects diagnostic traces using perf_events, a Linux OS technology. collect-linux requires admin privileges to capture kernel- and user-mode events, and by default, captures events from all processes.
         /// This Linux-only command includes the same .NET events as dotnet-trace collect, and it uses the kernel’s user_events mechanism to emit .NET events as perf events, enabling unification of user-space .NET events with kernel-space system events.
         /// </summary>
         internal int CollectLinux(CollectLinuxArgs args)
         {
-            if (!OperatingSystem.IsLinux())
+            if (!IsSupported())
             {
-                Console.Error.WriteLine("The collect-linux command is only supported on Linux.");
+                Console.Error.WriteLine("The collect-linux command is not supported on this platform.");
+                Console.Error.WriteLine("For requirements, please visit https://learn.microsoft.com/en-us/dotnet/core/diagnostics/dotnet-trace.");
                 return (int)ReturnCode.PlatformNotSupportedError;
             }
 

src/tests/dotnet-trace/CollectLinuxCommandFunctionalTests.cs

@@ -48,7 +48,7 @@ public void CollectLinuxCommandProviderConfigurationConsolidation(object testArg
         {
             MockConsole console = new(200, 30);
             int exitCode = Run(testArgs, console);
-            if (OperatingSystem.IsLinux())
+            if (CollectLinuxCommandHandler.IsSupported())
             {
                 Assert.Equal((int)ReturnCode.Ok, exitCode);
                 console.AssertSanitizedLinesEqual(CollectLinuxSanitizer, expectedLines);
@@ -57,7 +57,8 @@ public void CollectLinuxCommandProviderConfigurationConsolidation(object testArg
             {
                 Assert.Equal((int)ReturnCode.PlatformNotSupportedError, exitCode);
                 console.AssertSanitizedLinesEqual(null, new string[] {
-                    "The collect-linux command is only supported on Linux.",
+                    $"The collect-linux command is not supported on this platform.",
+                    $"For requirements, please visit https://learn.microsoft.com/en-us/dotnet/core/diagnostics/dotnet-trace."
                 });
             }
         }
@@ -68,7 +69,7 @@ public void CollectLinuxCommandProviderConfigurationConsolidation_Throws(object
         {
             MockConsole console = new(200, 30);
             int exitCode = Run(testArgs, console);
-            if (OperatingSystem.IsLinux())
+            if (CollectLinuxCommandHandler.IsSupported())
             {
                 Assert.Equal((int)ReturnCode.TracingError, exitCode);
                 console.AssertSanitizedLinesEqual(null, expectedException);
@@ -77,7 +78,8 @@ public void CollectLinuxCommandProviderConfigurationConsolidation_Throws(object
             {
                 Assert.Equal((int)ReturnCode.PlatformNotSupportedError, exitCode);
                 console.AssertSanitizedLinesEqual(null, new string[] {
-                    "The collect-linux command is only supported on Linux.",
+                    $"The collect-linux command is not supported on this platform.",
+                    $"For requirements, please visit https://learn.microsoft.com/en-us/dotnet/core/diagnostics/dotnet-trace."
                 });
             }
         }