FluentFTP: mono: Exception: Safe handle has been closed - fix included (read to end)

NOTE: I have a workaround by using version 32.3.1.0

**FTP OS: Unix type L8

FTP Server: ProFTPD

**Computer OS: RPi Linux Raspbian 5.4.51-v7+ armv7l and Mono 6.12.0.90

**FluentFTP Version: 33.0.2.0

Crash at connect (from my own logfile as no FTP logfile is produced) :

2020-11-16 08:40:26.783 InetSupport: Unknown Exception on FTPS connecting to ftp.meteo-wagenborgen.nl: Safe handle has been closed 2020-11-16 08:40:26.784 InetSupport: Failed FTPS connecting to ftp.meteo-wagenborgen.nl. Files will not be transferred 2020-11-16 08:40:26.784 Exception Unknown : Safe handle has been closed 2020-11-16 08:40:26.786 Data (cont): mscorlib 2020-11-16 08:40:26.798 Data: at System.Runtime.InteropServices.SafeHandle.DangerousAddRef (System.Boolean& success) [0x0001c] in <9f0df102fe6e4cfea29d2e46f585d8a5>:0 at System.Threading.WaitHandle.WaitOneNative (System.Runtime.InteropServices.SafeHandle waitableSafeHandle, System.UInt32 millisecondsTimeout, System.Boolean hasThreadAffinity, System.Boolean exitContext) [0x00008] in <9f0df102fe6e4cfea29d2e46f585d8a5>:0 at System.Threading.WaitHandle.InternalWaitOne (System.Runtime.InteropServices.SafeHandle waitableSafeHandle, System.Int64 millisecondsTimeout, System.Boolean hasThreadAffinity, System.Boolean exitContext) [0x00014] in <9f0df102fe6e4cfea29d2e46f585d8a5>:0 at System.Threading.WaitHandle.WaitOne (System.Int64 timeout, System.Boolean exitContext) [0x00000] in <9f0df102fe6e4cfea29d2e46f585d8a5>:0 at System.Threading.WaitHandle.WaitOne (System.Int32 millisecondsTimeout, System.Boolean exitContext) [0x00019] in <9f0df102fe6e4cfea29d2e46f585d8a5>:0 at FluentFTP.FtpSocketStream.Read (System.Byte[] buffer, System.Int32 offset, System.Int32 count) [0x0002e] in <d2e9f2023e584807be8dc039210ee032>:0 at FluentFTP.FtpSocketStream.ReadLine (System.Text.Encoding encoding) [0x00045] in <d2e9f2023e584807be8dc039210ee032>:0 at (wrapper remoting-invoke-with-check) FluentFTP.FtpSocketStream.ReadLine(System.Text.Encoding) at FluentFTP.FtpClient.GetReply () [0x0006e] in <d2e9f2023e584807be8dc039210ee032>:0 at FluentFTP.FtpClient.Execute (System.String command) [0x000da] in <d2e9f2023e584807be8dc039210ee032>:0 at FluentFTP.FtpClient.Authenticate (System.String userName, System.String password) [0x0000c] in <d2e9f2023e584807be8dc039210ee032>:0 at FluentFTP.FtpClient.Authenticate () [0x00017] in <d2e9f2023e584807be8dc039210ee032>:0 at FluentFTP.FtpClient.Connect () [0x00203] in <d2e9f2023e584807be8dc039210ee032>:0 at CumulusUtils.InetSupport…ctor (CumulusUtils.Support s) [0x003d9] in <a0cb7c0feca0466598eb79336532393a>:0 at CumulusUtils.CMXutils.Main (System.String[] args) [0x00103] in <a0cb7c0feca0466598eb79336532393a>:0 2020-11-16 08:40:26.799 Exiting - check log file

No FTP logs were produced as the connect fails

This happens in the connect after the following piece of C# code (the first time FluentFTP call is made):

     {
        try
        {
          clientFluentFTP = new FtpClient(hostname,
                                        username,
                                        password)
          {
            EncryptionMode = FtpEncryptionMode.Explicit,
            DataConnectionEncryption = true,
            SslProtocols = SslProtocols.None,
            DataConnectionType = PassiveFTP ? FtpDataConnectionType.EPSV : FtpDataConnectionType.PORT,
            Encoding = Encoding.UTF8,

            SocketKeepAlive = true,
            ValidateAnyCertificate = true,
            UploadDataType = FtpDataType.Binary
          };

          clientFluentFTP.Connect();
          Sup.LogDebugMessage($" InetSupport: FTPS activated.");
        }
        catch (Exception e) when (e is FtpAuthenticationException || e is FtpCommandException || e is FtpSecurityNotAvailableException)
        {
          Sup.LogDebugMessage($" InetSupport: Exception on FTPS connecting to {hostname}: {e.Message}");
          Sup.LogDebugMessage($" InetSupport: Failed FTPS connecting to {hostname}. Files will not be transferred");
          FTPvalid = false;
        }
        catch (Exception e)
        {
          Sup.LogDebugMessage($" InetSupport: Unknown Exception on FTPS connecting to {hostname}: {e.Message}");
          Sup.LogDebugMessage($" InetSupport: Failed FTPS connecting to {hostname}. Files will not be transferred");
          FTPvalid = false;
          throw;
        }
      }