Fix TUN mode cleanup on Linux/macOS (#8202)

v2rayN/ServiceLib/Manager/CoreAdminManager.cs

@@ -34,7 +34,7 @@ public class CoreAdminManager
         StringBuilder sb = new();
         sb.AppendLine("#!/bin/bash");
         var cmdLine = $"{fileName.AppendQuotes()} {string.Format(coreInfo.Arguments, Utils.GetBinConfigPath(configPath).AppendQuotes())}";
-        sb.AppendLine($"sudo -S {cmdLine}");
+        sb.AppendLine($"exec sudo -S -- {cmdLine}");
         var shFilePath = await FileManager.CreateLinuxShellFile("run_as_sudo.sh", sb.ToString(), true);
 
         var procService = new ProcessService(

v2rayN/ServiceLib/Sample/kill_as_sudo_linux_sh

@@ -47,6 +47,18 @@ echo "============================================"
 echo "Starting termination of process $PID and all its children"
 echo "============================================"
 
+# Try graceful termination first
+echo "Attempting graceful termination (SIGTERM) of PID: $PID"
+kill -15 "$PID" 2>/dev/null || true
+sleep 1
+# If still running, fall back to kill_children
+if ps -p $PID > /dev/null; then
+    echo "Process $PID did not exit after SIGTERM; proceeding with forced termination of its children and itself"
+else
+    echo "Process $PID exited cleanly after SIGTERM"
+    exit 0
+fi
+
 # Find and kill all child processes
 kill_children "$PID"
 

v2rayN/ServiceLib/Sample/kill_as_sudo_osx_sh

@@ -42,6 +42,20 @@ echo "============================================"
 echo "Starting termination of process $PID and all its descendants"
 echo "============================================"
 
+# Try graceful termination first
+echo "Attempting graceful termination (SIGTERM) of PID: $PID"
+kill -15 "$PID" 2>/dev/null || true
+sleep 1
+
+# If still running, fall back to kill_descendants
+# Use the macOS-native 'kill -0' check
+if kill -0 $PID 2>/dev/null; then
+    echo "Process $PID did not exit after SIGTERM; proceeding with forced termination of its descendants and itself"
+else
+    echo "Process $PID exited cleanly after SIGTERM"
+    exit 0
+fi
+
 # Find and kill all descendant processes
 kill_descendants "$PID"