Tried to add status and statusutf8 reader.

src/NTwain/TWAINWorkingGroup/TWAINH.cs

@@ -2488,7 +2488,7 @@ namespace TWAINWorkingGroup
   /// Translates the contents of Status into a localized UTF8string.
   /// </summary>
   [StructLayout(LayoutKind.Sequential, Pack = 2)]
-  public struct TW_STATUSUTF8
+  public partial struct TW_STATUSUTF8
   {
     public TW_STATUS Status;
     public uint Size;

src/NTwain/TWAINWorkingGroup/TWAINH_EXTRAS.cs

@@ -1,6 +1,8 @@
-using System;
+using NTwain;
+using System;
 using System.Globalization;
 using System.Runtime.InteropServices;
+using System.Text;
 
 namespace TWAINWorkingGroup
 {
@@ -600,6 +602,53 @@ namespace TWAINWorkingGroup
     }
   }
 
+  partial struct TW_STATUSUTF8
+  {
+    /// <summary>
+    /// Tries to read the text content and frees the memory.
+    /// </summary>
+    /// <param name="session"></param>
+    /// <returns></returns>
+    public string? ReadAndFree(TwainSession session)
+    {
+      string? val = null;
+      if (UTF8string != IntPtr.Zero && Size > 0)
+      {
+        var locked = session.Lock(UTF8string);
+        if (locked != IntPtr.Zero)
+        {
+          // does this work? who knows.
+          try
+          {
+#if NETFRAMEWORK
+          var bytes = new byte[Size];
+          Marshal.Copy(locked, bytes, 0, bytes.Length);
+          val = Encoding.UTF8.GetString(bytes);
+#else
+            val = Marshal.PtrToStringUTF8(locked, (int)Size);
+#endif
+          }
+          finally
+          {
+            session.Unlock(UTF8string);
+          }
+        }
+      }
+      Free(session);
+      return val;
+    }
+
+    /// <summary>
+    /// Frees the memory if necessary.
+    /// </summary>
+    /// <param name="session"></param>
+    public void Free(TwainSession session)
+    {
+      session.Free(UTF8string);
+      UTF8string = IntPtr.Zero;
+    }
+  }
+
   //partial struct TW_DEVICEEVENT
   //{
   //    public TWDE Event { get { return (TWDE)_event; } }

src/NTwain/Triplets/DATIdentity.cs

@@ -72,6 +72,7 @@ namespace NTwain.Triplets
     /// <summary>
     /// Gets the default data source.
     /// </summary>
+    /// <param name="ds"></param>
     /// <returns></returns>
     public STS GetDefault(out TW_IDENTITY_LEGACY ds)
     {
@@ -98,6 +99,7 @@ namespace NTwain.Triplets
     /// Gets the first available data source in an enumerating fashion 
     /// (use <see cref="GetNext"/> for subsequent ones).
     /// </summary>
+    /// <param name="ds"></param>
     /// <returns></returns>
     public STS GetFirst(out TW_IDENTITY_LEGACY ds)
     {
@@ -109,6 +111,7 @@ namespace NTwain.Triplets
     /// Gets the next available data source in an enumerating fashion (after using <see cref="GetFirst"/>).
     /// Ends when return values is <see cref="STS.ENDOFLIST"/>.
     /// </summary>
+    /// <param name="ds"></param>
     /// <returns></returns>
     public STS GetNext(out TW_IDENTITY_LEGACY ds)
     {

src/NTwain/Triplets/DATStatus.cs

@@ -0,0 +1,89 @@
+using System;
+using TWAINWorkingGroup;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.CONTROL"/> and <see cref="DAT.STATUS"/>.
+  /// </summary>
+  public class DATStatus : TripletBase
+  {
+    public DATStatus(TwainSession session) : base(session)
+    {
+    }
+
+    /// <summary>
+    /// Gets the current status for the DSM.
+    /// </summary>
+    /// <param name="status"></param>
+    /// <returns></returns>
+    public STS GetForDSM(out TW_STATUS status)
+    {
+      status = default;
+      var rc = STS.FAILURE;
+      if (TwainPlatform.IsWindows)
+      {
+        var app = Session.AppIdentity;
+        if (TwainPlatform.Is32bit && TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.WindowsTwain32DsmEntryStatusState3(ref app, IntPtr.Zero, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.WindowsTwaindsmDsmEntryStatusState3(ref app, IntPtr.Zero, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+      }
+      else if (TwainPlatform.IsMacOSX)
+      {
+        TW_IDENTITY_MACOSX app = Session.AppIdentity;
+        if (TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.MacosxTwainDsmEntryStatusState3(ref app, IntPtr.Zero, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.MacosxTwaindsmDsmEntryStatusState3(ref app, IntPtr.Zero, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+      }
+      return rc;
+    }
+
+    /// <summary>
+    /// Gets the status for the current source.
+    /// </summary>
+    /// <param name="status"></param>
+    /// <returns></returns>
+    public STS GetForDS(out TW_STATUS status)
+    {
+      status = default;
+      var ds = Session.CurrentSource;
+      var rc = STS.FAILURE;
+      if (TwainPlatform.IsWindows)
+      {
+        var app = Session.AppIdentity;
+        if (TwainPlatform.Is32bit && TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.WindowsTwain32DsmEntryStatus(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.WindowsTwaindsmDsmEntryStatus(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+      }
+      else if (TwainPlatform.IsMacOSX)
+      {
+        TW_IDENTITY_MACOSX app = Session.AppIdentity;
+        TW_IDENTITY_MACOSX osxds = ds;
+        if (TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.MacosxTwainDsmEntryStatus(ref app, ref osxds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.MacosxTwaindsmDsmEntryStatus(ref app, ref osxds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref status);
+        }
+      }
+      return rc;
+    }
+  }
+}

src/NTwain/Triplets/DATStatusUtf8.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Text;
+using TWAINWorkingGroup;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.CONTROL"/> and <see cref="DAT.STATUSUTF8"/>.
+  /// </summary>
+  public class DATStatusUtf8 : TripletBase
+  {
+    public DATStatusUtf8(TwainSession session) : base(session)
+    {
+
+    }
+
+    /// <summary>
+    /// Gets the extended text info for a previously received <see cref="TW_STATUS"/>.
+    /// If this is called you should try to extract the string value from it once
+    /// with <see cref="TW_STATUSUTF8.ReadAndFree"/> or call <see cref="TW_STATUSUTF8.Free"/>
+    /// so there's no memory leak.
+    /// </summary>
+    /// <param name="status"></param>
+    /// <param name="extendedStatus"></param>
+    /// <returns></returns>
+    public STS Get(TW_STATUS status, out TW_STATUSUTF8 extendedStatus)
+    {
+      extendedStatus = new TW_STATUSUTF8 { Status = status };
+      var rc = STS.FAILURE;
+      if (TwainPlatform.IsWindows)
+      {
+        var app = Session.AppIdentity;
+        var ds = Session.CurrentSource;
+        if (TwainPlatform.Is32bit && TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.WindowsTwain32DsmEntryStatusutf8(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref extendedStatus);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.WindowsTwaindsmDsmEntryStatusutf8(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref extendedStatus);
+        }
+      }
+      else if (TwainPlatform.IsMacOSX)
+      {
+        TW_IDENTITY_MACOSX app = Session.AppIdentity;
+        TW_IDENTITY_MACOSX ds = Session.CurrentSource;
+        if (TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.MacosxTwainDsmEntryStatusutf8(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref extendedStatus);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.MacosxTwaindsmDsmEntryStatusutf8(ref app, ref ds, DG.CONTROL, DAT.IDENTITY, MSG.GET, ref extendedStatus);
+        }
+      }
+      return rc;
+    }
+
+  }
+}

src/NTwain/Triplets/DGControl.cs

@@ -18,5 +18,11 @@
     private DATIdentity? _identity;
     public DATIdentity Identity => _identity ??= new DATIdentity(Session);
 
+    private DATStatus? _status;
+    public DATStatus Status => _status ??= new DATStatus(Session);
+
+    private DATStatusUtf8? _statusUtf8;
+    public DATStatusUtf8 StatusUtf8 => _statusUtf8 ??= new DATStatusUtf8(Session);
+
   }
 }