Made it so TidyManaged will automatically switch between the 32bit and 64bit version of libtidy.

Document.cs

@@ -37,6 +37,8 @@ namespace TidyManaged
 	/// </summary>
 	public class Document : IDisposable
 	{
+        internal static IPInvoke PInvoke = IntPtr.Size == 8 ? new PInvoke64() as IPInvoke : new PInvoke32() as IPInvoke;
+
 		#region Constructors
 
 		Document()
@@ -939,26 +941,50 @@ public bool WriteBack
 
 		#region Methods
 
-		/// <summary>
-		/// Parses input markup, and executes configured cleanup and repair operations.
-		/// </summary>
-		public void CleanAndRepair()
-		{
-			if (fromString)
-			{
-				EncodingType tempEnc = this.InputCharacterEncoding;
-				this.InputCharacterEncoding = EncodingType.Utf8;
-				PInvoke.tidyParseString(this.handle, this.htmlString);
-				this.InputCharacterEncoding = tempEnc;
-			}
-			else
-			{
-				InputSource input = new InputSource(this.stream);
-				PInvoke.tidyParseSource(this.handle, ref input.TidyInputSource);
-			}
-			PInvoke.tidyCleanAndRepair(this.handle);
-			cleaned = true;
-		}
+        /// <summary>
+        /// Parses input markup, and executes configured cleanup and repair operations.
+        /// </summary>
+        /// <returns>A log of the errors encountered during the CleanAndRepair operation.</returns>
+		public string CleanAndRepair()
+		{
+            using (Stream stream = new MemoryStream())
+            {
+                CleanAndRepair(stream);
+                stream.Seek(0, SeekOrigin.Begin);
+                using (StreamReader reader = new StreamReader(stream))
+                {
+                    return reader.ReadToEnd();
+                }
+            }
+		}
+
+        /// <summary>
+        /// Parses input markup, and executes configured cleanup and repair operations.
+        /// </summary>
+        /// <param name="logStream">A stream to which errors encountered during the CleanAndRepair operation will be written to.</param>
+        public void CleanAndRepair(Stream logStream)
+        {
+            //Config Error
+            EncodingType tempOutEnc = this.OutputCharacterEncoding;
+            this.OutputCharacterEncoding = EncodingType.Utf8;
+            OutputSink sink = new OutputSink(logStream);
+            PInvoke.tidySetErrorSink(this.handle, ref sink.TidyOutputSink);
+            if (fromString)
+            {
+                EncodingType tempEnc = this.InputCharacterEncoding;
+                this.InputCharacterEncoding = EncodingType.Utf8;
+                PInvoke.tidyParseString(this.handle, this.htmlString);
+                this.InputCharacterEncoding = tempEnc;
+            }
+            else
+            {
+                InputSource input = new InputSource(this.stream);
+                PInvoke.tidyParseSource(this.handle, ref input.TidyInputSource);
+            }
+            PInvoke.tidyCleanAndRepair(this.handle);
+            this.OutputCharacterEncoding = tempOutEnc;
+            cleaned = true;
+        }
 
 		/// <summary>
 		/// Saves the processed markup to a string.

Interop/IPInvoke.cs

@@ -0,0 +1,25 @@
+using System;
+namespace TidyManaged.Interop
+{
+    internal interface IPInvoke
+    {
+        int tidyCleanAndRepair(IntPtr tdoc);
+        IntPtr tidyCreate();
+        bool tidyOptGetBool(IntPtr tdoc, TidyOptionId optId);
+        uint tidyOptGetInt(IntPtr tdoc, TidyOptionId optId);
+        IntPtr tidyOptGetValue(IntPtr tdoc, TidyOptionId optId);
+        string tidyOptGetValueString(IntPtr tdoc, TidyOptionId optId);
+        bool tidyOptSetBool(IntPtr tdoc, TidyOptionId optId, bool val);
+        bool tidyOptSetInt(IntPtr tdoc, TidyOptionId optId, uint val);
+        bool tidyOptSetValue(IntPtr tdoc, TidyOptionId optId, string val);
+        int tidyParseFile(IntPtr tdoc, string filename);
+        int tidyParseSource(IntPtr tdoc, ref TidyInputSource source);
+        int tidyParseString(IntPtr tdoc, string content);
+        void tidyRelease(IntPtr tdoc);
+        IntPtr tidyReleaseDate();
+        int tidySaveFile(IntPtr tdoc, string filname);
+        int tidySaveSink(IntPtr tdoc, ref TidyOutputSink sink);
+        int tidySaveString(IntPtr tdoc, IntPtr buffer, ref uint buflen);
+        int tidySetErrorSink(IntPtr tdoc, ref TidyOutputSink sink);
+    }
+}

Interop/PInvoke32.cs

@@ -0,0 +1,181 @@
+// Copyright (c) 2009 Mark Beaton
+//
+// Permission is hereby granted, free of charge, to any person
+// obtaining a copy of this software and associated documentation
+// files (the "Software"), to deal in the Software without
+// restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace TidyManaged.Interop
+{
+    internal class PInvoke32 : IPInvoke
+	{
+		[DllImport("libtidy32.dll")]
+		internal static extern IntPtr tidyCreate();
+
+		[DllImport("libtidy32.dll")]
+		internal static extern void tidyRelease(IntPtr tdoc);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern IntPtr tidyReleaseDate();
+
+		[DllImport("libtidy32.dll")]
+		internal static extern IntPtr tidyOptGetValue(IntPtr tdoc, TidyOptionId optId);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern bool tidyOptSetValue(IntPtr tdoc, TidyOptionId optId, string val);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern uint tidyOptGetInt(IntPtr tdoc, TidyOptionId optId);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern bool tidyOptSetInt(IntPtr tdoc, TidyOptionId optId, uint val);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern bool tidyOptGetBool(IntPtr tdoc, TidyOptionId optId);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern bool tidyOptSetBool(IntPtr tdoc, TidyOptionId optId, bool val);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidyParseFile(IntPtr tdoc, string filename);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidyParseString(IntPtr tdoc, string content);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidyParseSource(IntPtr tdoc, ref TidyInputSource source);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidyCleanAndRepair(IntPtr tdoc);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidySaveFile(IntPtr tdoc, string filname);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidySaveString(IntPtr tdoc, IntPtr buffer, ref uint buflen);
+
+		[DllImport("libtidy32.dll")]
+		internal static extern int tidySaveSink(IntPtr tdoc, ref TidyOutputSink sink);
+
+        [DllImport("libtidy32.dll")]
+        internal static extern int tidySetErrorSink(IntPtr tdoc, ref TidyOutputSink sink);
+
+		internal static string tidyOptGetValueString(IntPtr tdoc, TidyOptionId optId)
+		{
+			return Marshal.PtrToStringAnsi(tidyOptGetValue(tdoc, optId));
+		}
+
+        #region IPInvoke Members
+
+        int IPInvoke.tidyCleanAndRepair(IntPtr tdoc)
+        {
+            return tidyCleanAndRepair(tdoc);
+        }
+
+        IntPtr IPInvoke.tidyCreate()
+        {
+            return tidyCreate();
+        }
+
+        bool IPInvoke.tidyOptGetBool(IntPtr tdoc, TidyOptionId optId)
+        {
+            return tidyOptGetBool(tdoc, optId);
+        }
+
+        uint IPInvoke.tidyOptGetInt(IntPtr tdoc, TidyOptionId optId)
+        {
+            return tidyOptGetInt(tdoc, optId);
+        }
+
+        IntPtr IPInvoke.tidyOptGetValue(IntPtr tdoc, TidyOptionId optId)
+        {
+            return tidyOptGetValue(tdoc, optId);
+        }
+
+        string IPInvoke.tidyOptGetValueString(IntPtr tdoc, TidyOptionId optId)
+        {
+            return tidyOptGetValueString(tdoc, optId);
+        }
+
+        bool IPInvoke.tidyOptSetBool(IntPtr tdoc, TidyOptionId optId, bool val)
+        {
+            return tidyOptSetBool(tdoc, optId, val);
+        }
+
+        bool IPInvoke.tidyOptSetInt(IntPtr tdoc, TidyOptionId optId, uint val)
+        {
+            return tidyOptSetInt(tdoc, optId, val);
+        }
+
+        bool IPInvoke.tidyOptSetValue(IntPtr tdoc, TidyOptionId optId, string val)
+        {
+            return tidyOptSetValue(tdoc, optId, val);
+        }
+
+        int IPInvoke.tidyParseFile(IntPtr tdoc, string filename)
+        {
+            return tidyParseFile(tdoc, filename);
+        }
+
+        int IPInvoke.tidyParseSource(IntPtr tdoc, ref TidyInputSource source)
+        {
+            return tidyParseSource(tdoc, ref source);
+        }
+
+        int IPInvoke.tidyParseString(IntPtr tdoc, string content)
+        {
+            return tidyParseString(tdoc, content);
+        }
+
+        void IPInvoke.tidyRelease(IntPtr tdoc)
+        {
+            tidyRelease(tdoc);
+        }
+
+        IntPtr IPInvoke.tidyReleaseDate()
+        {
+            return tidyReleaseDate();
+        }
+
+        int IPInvoke.tidySaveFile(IntPtr tdoc, string filname)
+        {
+            return tidySaveFile(tdoc, filname);
+        }
+
+        int IPInvoke.tidySaveSink(IntPtr tdoc, ref TidyOutputSink sink)
+        {
+            return tidySaveSink(tdoc, ref sink);
+        }
+
+        int IPInvoke.tidySaveString(IntPtr tdoc, IntPtr buffer, ref uint buflen)
+        {
+            return tidySaveString(tdoc, buffer, ref buflen);
+        }
+
+        int IPInvoke.tidySetErrorSink(IntPtr tdoc, ref TidyOutputSink sink)
+        {
+            return tidySetErrorSink(tdoc, ref sink);
+        }
+
+        #endregion
+    }
+}