Replace thread with event

src/WinSW.Core/Util/ProcessHelper.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Diagnostics;
-using System.Threading;
 using log4net;
 using static WinSW.Native.ProcessApis;
 
@@ -194,32 +193,20 @@ namespace WinSW.Util
             // monitor the completion of the process
             if (callback != null)
             {
-                StartThread(() =>
-                {
-                    processToStart.WaitForExit();
-                    callback(processToStart);
-                });
-            }
-        }
-
-        /// <summary>
-        /// Starts a thread that protects the execution with a try/catch block.
-        /// It appears that in .NET, unhandled exception in any thread causes the app to terminate
-        /// http://msdn.microsoft.com/en-us/library/ms228965.aspx
-        /// </summary>
-        public static void StartThread(ThreadStart main)
-        {
-            new Thread(() =>
+                processToStart.Exited += (_, _) =>
                 {
                     try
                     {
-                    main();
+                        callback(processToStart);
                     }
                     catch (Exception e)
                     {
                         Logger.Error("Thread failed unexpectedly", e);
                     }
-            }).Start();
+                };
+
+                processToStart.EnableRaisingEvents = true;
+            }
         }
     }
 

src/WinSW.Core/WinSW.Core.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>net461;netcoreapp3.1</TargetFrameworks>
-    <LangVersion>latest</LangVersion>
+    <LangVersion>preview</LangVersion>
     <Nullable>enable</Nullable>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>

src/WinSW/WrapperService.cs

@@ -297,6 +297,7 @@ namespace WinSW
             this.LogEvent("Stopping " + this.descriptor.Id);
             Log.Info("Stopping " + this.descriptor.Id);
             this.orderlyShutdown = true;
+            this.process.EnableRaisingEvents = false;
 
             if (stopArguments is null)
             {