Program.cs

using log4net;
using log4net.Config;
using log4net.Repository;
using Plus.Core;
using System;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Threading;

namespace Plus
{
    public static class Program
    {
        public const int SC_CLOSE = 0xF060;

        [DllImport("Kernel32")]
        private static extern bool SetConsoleCtrlHandler(EventHandler handler, bool add);

        [DllImport("user32.dll")]
        public static extern int DeleteMenu(IntPtr hMenu, int nPosition, int wFlags);

        [DllImport("user32.dll")]
        private static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert);

        [DllImport("kernel32.dll", ExactSpelling = true)]
        private static extern IntPtr GetConsoleWindow();

        private static readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        public static void Main(string[] args)
        {
            ILoggerRepository repository = LogManager.GetRepository(Assembly.GetCallingAssembly());
            var fileInfo = new FileInfo(@"log4net.config");

            XmlConfigurator.Configure(repository, fileInfo);

            Console.ForegroundColor = ConsoleColor.White;
            Console.CursorVisible = false;
            AppDomain currentDomain = AppDomain.CurrentDomain;
            currentDomain.UnhandledException += MyHandler;

            PosixSignalRegistration.Create(PosixSignal.SIGTERM, HandleShutdownSignal);
            PosixSignalRegistration.Create(PosixSignal.SIGINT, HandleShutdownSignal);
            PosixSignalRegistration.Create(PosixSignal.SIGQUIT, HandleShutdownSignal);

            PlusEnvironment.Initialize();

            if (Environment.UserInteractive && !Console.IsInputRedirected) {
                while (true) {
                    if (Console.ReadKey(true).Key == ConsoleKey.Enter) {
                        Console.Write("plus> ");

                        string? input = Console.ReadLine();

                        if (!string.IsNullOrWhiteSpace(input)) {
                            string s = input.Split(' ')[0];

                            ConsoleCommands.InvokeCommand(s);
                        }
                    }
                }
            } else {
                Thread.Sleep(Timeout.Infinite);
            }
        }

        private static void HandleShutdownSignal(PosixSignalContext context)
        {
            context.Cancel = true;
            log.Info($"Received {context.Signal}, performing graceful shutdown...");
            PlusEnvironment.PerformShutDown();
        }

        private static void MyHandler(object sender, UnhandledExceptionEventArgs args)
        {
            var e = (Exception)args.ExceptionObject;
            //Logger.LogCriticalException("SYSTEM CRITICAL EXCEPTION: " + e);
            PlusEnvironment.PerformShutDown();
        }

        private enum CtrlType
        {
            CTRL_C_EVENT = 0,
            CTRL_BREAK_EVENT = 1,
            CTRL_CLOSE_EVENT = 2,
            CTRL_LOGOFF_EVENT = 5,
            CTRL_SHUTDOWN_EVENT = 6
        }

        private delegate bool EventHandler(CtrlType sig);
    }
}