--- E:/lib/boost_1_53_0/1.53/boost/asio/detail/impl/win_iocp_handle_service.ipp_patch	Mon Sep 16 14:53:40 2013
+++ E:/lib/boost_1_53_0/1.53/boost/asio/detail/impl/win_iocp_handle_service.ipp	Sun Jan 15 06:46:25 2012
@@ -364,21 +364,22 @@
     // A request to write 0 bytes on a handle is a no-op.
     iocp_service_.on_completion(op);
   }
   else
   {
+    DWORD bytes_transferred = 0;
     op->Offset = offset & 0xFFFFFFFF;
     op->OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
     BOOL ok = ::WriteFile(impl.handle_,
         boost::asio::buffer_cast<LPCVOID>(buffer),
         static_cast<DWORD>(boost::asio::buffer_size(buffer)),
-        NULL, op);
+        &bytes_transferred, op);
     DWORD last_error = ::GetLastError();
     if (!ok && last_error != ERROR_IO_PENDING
         && last_error != ERROR_MORE_DATA)
     {
-      iocp_service_.on_completion(op, last_error, NULL);
+      iocp_service_.on_completion(op, last_error, bytes_transferred);
     }
     else
     {
       iocp_service_.on_pending(op);
     }
@@ -471,21 +472,22 @@
     // A request to read 0 bytes on a handle is a no-op.
     iocp_service_.on_completion(op);
   }
   else
   {
+    DWORD bytes_transferred = 0;
     op->Offset = offset & 0xFFFFFFFF;
     op->OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
     BOOL ok = ::ReadFile(impl.handle_,
         boost::asio::buffer_cast<LPVOID>(buffer),
         static_cast<DWORD>(boost::asio::buffer_size(buffer)),
-        NULL, op);
+        &bytes_transferred, op);
     DWORD last_error = ::GetLastError();
     if (!ok && last_error != ERROR_IO_PENDING
         && last_error != ERROR_MORE_DATA)
     {
-      iocp_service_.on_completion(op, last_error, NULL);
+      iocp_service_.on_completion(op, last_error, bytes_transferred);
     }
     else
     {
       iocp_service_.on_pending(op);
     }