diff --git a/ftk/src/ftk.h b/ftk/src/ftk.h
index e3fc976..644660c 100644
--- a/ftk/src/ftk.h
+++ b/ftk/src/ftk.h
@@ -1586,10 +1586,8 @@
 			FLMUINT64				ui64WriteOffset,
 			FLMUINT					uiBytesToWrite,
 			const void *			pvBuffer,
-			FLMUINT					uiBufferSize,
 			IF_IOBuffer *			pBufferObj,
-			FLMUINT *				puiBytesWritten = NULL,
-			FLMBOOL					bZeroFill = TRUE) = 0;
+			FLMUINT *				puiBytesWritten = NULL) = 0;
 
 		virtual RCODE FLMAPI close( void) = 0;
 
diff --git a/ftk/src/ftkerror.cpp b/ftk/src/ftkerror.cpp
index 483eff1..37ca5cd 100644
--- a/ftk/src/ftkerror.cpp
+++ b/ftk/src/ftkerror.cpp
@@ -41,6 +41,8 @@ RCODE FLMAPI f_makeErr(
 	{
 		return( NE_FLM_OK);
 	}
+	
+	f_assert( rc != NE_FLM_MEM);
 
 #if defined( FLM_DEBUG)
 	if( bAssert)
@@ -83,7 +85,7 @@ RCODE FLMAPI f_mapPlatformError(
 
 		case EINVAL:
 		{
-			return( RC_SET( NE_FLM_IO_PATH_TOO_LONG));
+			return( RC_SET_AND_ASSERT( NE_FLM_IO_PATH_TOO_LONG));
 		}
 
 		case EIO:
diff --git a/ftk/src/ftkfsys.cpp b/ftk/src/ftkfsys.cpp
index 1179351..15d1bfd 100644
--- a/ftk/src/ftkfsys.cpp
+++ b/ftk/src/ftkfsys.cpp
@@ -1980,7 +1980,7 @@ RCODE FLMAPI F_FileSystem::pathAppend(
 
 			if (uiStrLen + 2 + f_strlen( pszPathComponent) > F_PATH_MAX_SIZE)
 			{
-				return RC_SET( NE_FLM_IO_PATH_TOO_LONG);
+				return RC_SET_AND_ASSERT( NE_FLM_IO_PATH_TOO_LONG);
 			}
 
 			pszEnd++;
@@ -1997,7 +1997,7 @@ RCODE FLMAPI F_FileSystem::pathAppend(
 
 			if (uiStrLen + 1 + f_strlen( pszPathComponent) > F_PATH_MAX_SIZE)
 			{
-				return RC_SET( NE_FLM_IO_PATH_TOO_LONG);
+				return RC_SET_AND_ASSERT( NE_FLM_IO_PATH_TOO_LONG);
 			}
 		}
 
@@ -2089,7 +2089,7 @@ RCODE FLMAPI F_FileSystem::pathToStorageString(
 
 	if (f_strlen( pszRealPath) >= F_PATH_MAX_SIZE)
 	{
-		rc = RC_SET( NE_FLM_IO_PATH_TOO_LONG);
+		rc = RC_SET_AND_ASSERT( NE_FLM_IO_PATH_TOO_LONG);
 		goto Exit;
 	}
 
diff --git a/ftk/src/ftkiobuf.cpp b/ftk/src/ftkiobuf.cpp
index c4f16b7..cb4b6c6 100644
--- a/ftk/src/ftkiobuf.cpp
+++ b/ftk/src/ftkiobuf.cpp
@@ -573,13 +573,40 @@ RCODE F_IOBuffer::waitToComplete( void)
 #if defined( FLM_LINUX) || defined( FLM_SOLARIS)
 	if( m_aio.aio_fildes != -1)
 	{
-		const struct aiocb *		pAio = &m_aio;
+		FLMINT						iAsyncResult;
+		const struct aiocb *		ppAio[ 1];
 		
-		if( aio_suspend( &pAio, 1, NULL) == -1)
-		{
-			rc = f_mapPlatformError( errno, NE_FLM_MEM);
-		}
+		ppAio[ 0] = &m_aio;
 
+		for( ;;)
+		{
+			aio_suspend( ppAio, 1, NULL);
+			iAsyncResult = aio_error( &m_aio);
+	
+			if( !iAsyncResult)
+			{
+				if( (iAsyncResult = aio_return( &m_aio)) < 0)
+				{
+					f_assert( 0);
+					rc = f_mapPlatformError( errno, NE_FLM_WRITING_FILE);
+					goto WriteComplete;
+				}
+					
+				break;
+			}
+				
+			if( iAsyncResult == EINTR || iAsyncResult == EINPROGRESS)
+			{
+				continue;
+			}
+					
+			f_assert( 0);
+			rc = f_mapPlatformError( errno, NE_FLM_WRITING_FILE);
+			goto WriteComplete;
+		}
+		
+WriteComplete:
+		
 		notifyComplete( rc);
 	}
 #endif
diff --git a/ftk/src/ftknlm.cpp b/ftk/src/ftknlm.cpp
index 4516161..6cd670c 100644
--- a/ftk/src/ftknlm.cpp
+++ b/ftk/src/ftknlm.cpp
@@ -3188,8 +3188,7 @@ RCODE FLMAPI F_FileHdl::sectorWrite(
 	const void *		pvBuffer,
 	FLMUINT				uiBufferSize,
 	void *				pvBufferObj,
-	FLMUINT *			puiBytesWrittenRV,
-	FLMBOOL				bZeroFill)
+	FLMUINT *			puiBytesWrittenRV)
 {
 	RCODE					rc = NE_FLM_OK;
 	IF_IOBuffer *		pBufferObj = (IF_IOBuffer *)pvBufferObj;
@@ -3199,7 +3198,7 @@ RCODE FLMAPI F_FileHdl::sectorWrite(
 	if ( m_bDoDirectIO)
 	{
 		if( RC_BAD( rc = _directIOSectorWrite( (FLMUINT)ui64WriteOffset, 
-			uiBytesToWrite, pvBuffer, pBufferObj, puiBytesWrittenRV, bZeroFill)))
+			uiBytesToWrite, pvBuffer, pBufferObj, puiBytesWrittenRV)))
 		{
 			goto Exit;
 		}
@@ -3235,8 +3234,7 @@ RCODE F_FileHdl::_directIOSectorWrite(
 	FLMUINT			uiBytesToWrite,
 	const void *	pvBuffer,
 	IF_IOBuffer *	pBufferObj,
-	FLMUINT *		puiBytesWrittenRV,
-	FLMBOOL			bZeroFill)
+	FLMUINT *		puiBytesWrittenRV)
 {
 	RCODE		rc = NE_FLM_OK;
 	LONG		lStartSector;
@@ -3271,14 +3269,11 @@ RCODE F_FileHdl::_directIOSectorWrite(
 
 		lSectorCount++;
 
-		if (bZeroFill)
-		{
-			// Zero out the part of the buffer that was not included in
-			// uiBytesToWrite - because it will still be written to disk.
+		// Zero out the part of the buffer that was not included in
+		// uiBytesToWrite - because it will still be written to disk.
 
-			f_memset( &pucBuffer [uiBytesToWrite], 0,
-						(FLMUINT)(FLM_NLM_SECTOR_SIZE - (uiBytesToWrite % FLM_NLM_SECTOR_SIZE)));
-		}
+		f_memset( &pucBuffer [uiBytesToWrite], 0,
+					(FLMUINT)(FLM_NLM_SECTOR_SIZE - (uiBytesToWrite % FLM_NLM_SECTOR_SIZE)));
 	}
 
 	if( RC_BAD( rc = writeSectors( (void *)pvBuffer, lStartSector, lSectorCount,
diff --git a/ftk/src/ftksys.h b/ftk/src/ftksys.h
index 9662bc5..cec844c 100644
--- a/ftk/src/ftksys.h
+++ b/ftk/src/ftksys.h
@@ -532,7 +532,7 @@
 			if (m_bDoDirectIO)
 			{
 				return( directRead( ui64ReadOffset, uiBytesToRead,
-						pvBuffer, TRUE, puiBytesReadRV));
+						pvBuffer, puiBytesReadRV));
 			}
 			else
 			{
@@ -545,17 +545,13 @@
 			FLMUINT64		ui64WriteOffset,
 			FLMUINT			uiBytesToWrite,
 			const void *	pvBuffer,
-			FLMUINT			uiBufferSize,
 			IF_IOBuffer *	pBufferObj,
-			FLMUINT *		puiBytesWrittenRV,
-			FLMBOOL			bZeroFill = TRUE)
+			FLMUINT *		puiBytesWrittenRV)
 		{
-			F_UNREFERENCED_PARM( uiBufferSize);
-			
 			if (m_bDoDirectIO)
 			{
 				return( directWrite( ui64WriteOffset, uiBytesToWrite,
-						pvBuffer, pBufferObj, TRUE, bZeroFill, puiBytesWrittenRV));
+						pvBuffer, pBufferObj, puiBytesWrittenRV));
 			}
 			else
 			{
@@ -631,7 +627,6 @@
 			FLMUINT64		uiOffset,
 			FLMUINT			uiLength,
 			void *			pvBuffer,
-			FLMBOOL			bBuffHasFullSectors,
 			FLMUINT *		puiBytesRead);
 	
 		RCODE directWrite(
@@ -639,8 +634,6 @@
 			FLMUINT			uiLength,
 			const void *	pvBuffer,
 			IF_IOBuffer *	pBufferObj,
-			FLMBOOL			bBuffHasFullSectors,
-			FLMBOOL			bZeroFill,
 			FLMUINT *		puiBytesWritten);
 	
 		FINLINE FLMUINT64 roundToNextSector(
@@ -736,17 +729,13 @@
 			FLMUINT64			ui64WriteOffset,
 			FLMUINT				uiBytesToWrite,
 			const void *		pvBuffer,
-			FLMUINT				uiBufferSize,
 			IF_IOBuffer *		pBufferObj,
-			FLMUINT *			puiBytesWrittenRV,
-			FLMBOOL				bZeroFill = TRUE)
+			FLMUINT *			puiBytesWrittenRV)
 		{
-			F_UNREFERENCED_PARM( uiBufferSize);
-			
 			if( m_bDoDirectIO)
 			{
 				return( directWrite( ui64WriteOffset, uiBytesToWrite, 
-					pvBuffer, pBufferObj, puiBytesWrittenRV, TRUE, bZeroFill));
+					pvBuffer, pBufferObj, puiBytesWrittenRV));
 			}
 			else
 			{
@@ -826,7 +815,6 @@
 			FLMUINT64			ui64ReadOffset,
 			FLMUINT				uiBytesToRead,	
 			void *				pvBuffer,
-			FLMBOOL				bBuffHasFullSectors,
 			FLMUINT *			puiBytesRead);
 	
 		RCODE directWrite(
@@ -834,9 +822,7 @@
 			FLMUINT				uiBytesToWrite,
 			const void *		pvBuffer,
 			IF_IOBuffer *		pBufferObj,
-			FLMUINT *			puiBytesWrittenRV,
-			FLMBOOL				bBuffHasFullSectors,
-			FLMBOOL				bZeroFill);
+			FLMUINT *			puiBytesWrittenRV);
 		
 		RCODE allocAlignedBuffer( void);
 		
@@ -911,10 +897,8 @@
 			FLMUINT64			ui64WriteOffset,
 			FLMUINT				uiBytesToWrite,
 			const void *		pvBuffer,
-			FLMUINT				uiBufferSize,
 			IF_IOBuffer *		pBufferObj,
-			FLMUINT *			puiBytesWrittenRV,
-			FLMBOOL				bZeroFill = TRUE);
+			FLMUINT *			puiBytesWrittenRV);
 	
 		RCODE FLMAPI close( void);
 													
@@ -1020,8 +1004,7 @@
 			FLMUINT				uiBytesToWrite,
 			const void *		pvBuffer,
 			IF_IOBuffer *		pBufferObj,
-			FLMUINT *			puiBytesWrittenRV,
-			FLMBOOL				bZeroFill);
+			FLMUINT *			puiBytesWrittenRV);
 	
 		char *					m_pszIoPath;
 		FLMBOOL					m_bDeleteOnClose;
diff --git a/ftk/src/ftkunix.cpp b/ftk/src/ftkunix.cpp
index 4741a6b..8fdc9bc 100644
--- a/ftk/src/ftkunix.cpp
+++ b/ftk/src/ftkunix.cpp
@@ -82,7 +82,6 @@ F_FileHdl::F_FileHdl()
 	m_pszFileName = NULL;
 	
 	m_fd = -1;
-	m_bDoDirectIO = FALSE;
 	m_uiExtendSize = 0;
 	m_uiBytesPerSector = 0;
 	m_ui64NotOnSectorBoundMask = 0;
@@ -129,6 +128,7 @@ RCODE F_FileHdl::openOrCreate(
 	char					szSaveFileName[ F_PATH_MAX_SIZE];
 	int         		openFlags = O_RDONLY;
 	IF_FileSystem *	pFileSystem = f_getFileSysPtr();
+	struct stat			filestats;
 
 #if defined( FLM_LINUX) || defined( FLM_SOLARIS)
 	bDoDirectIO = (uiAccess & FLM_IO_DIRECT) ? TRUE : FALSE;
@@ -176,15 +176,6 @@ RCODE F_FileHdl::openOrCreate(
 
 	if( bDoDirectIO)
 	{
-		if( RC_BAD( rc = pFileSystem->getSectorSize(
-			pszFileName, &m_uiBytesPerSector)))
-		{
-			goto Exit;
-		}
-		
-		m_ui64NotOnSectorBoundMask = m_uiBytesPerSector - 1;
-		m_ui64GetSectorBoundMask = ~m_ui64NotOnSectorBoundMask;
-
 		// Can't do direct IO if the block size isn't a multiple of
 		// the sector size.
 
@@ -267,6 +258,15 @@ Retry_Create:
 	}
 #endif
 	
+	if( fstat( m_fd, &filestats) != 0)
+	{
+		rc = f_mapPlatformError( errno, NE_FLM_OPENING_FILE);
+		goto Exit;
+	}
+	
+	m_uiBytesPerSector = filestats.st_blksize;
+	m_ui64NotOnSectorBoundMask = m_uiBytesPerSector - 1;
+	m_ui64GetSectorBoundMask = ~m_ui64NotOnSectorBoundMask;
 	m_bDoDirectIO = bDoDirectIO;
 
 Exit:
@@ -592,7 +592,6 @@ RCODE F_FileHdl::directRead(
 	FLMUINT64		ui64ReadOffset,
 	FLMUINT			uiBytesToRead,	
    void *			pvBuffer,
-	FLMBOOL			bBuffHasFullSectors,
 	FLMUINT *		puiBytesRead)
 {
 	RCODE				rc = NE_FLM_OK;
@@ -626,9 +625,8 @@ RCODE F_FileHdl::directRead(
 		// one (if not already allocated), and use it.
 
 		if( (ui64ReadOffset & m_ui64NotOnSectorBoundMask) ||
-			 (((FLMUINT64)(FLMUINT)pucDestBuffer) & m_ui64NotOnSectorBoundMask) ||
-			 ((uiBytesToRead & m_ui64NotOnSectorBoundMask) &&
-			  !bBuffHasFullSectors))
+			 (uiBytesToRead & m_ui64NotOnSectorBoundMask) ||
+			 (((FLMUINT64)(FLMUINT)pucDestBuffer) & m_ui64NotOnSectorBoundMask))
 		{
 			if( !m_pucAlignedBuff)
 			{
@@ -755,7 +753,7 @@ RCODE FLMAPI F_FileHdl::read(
 	if( m_bDoDirectIO)
 	{
 		rc = directRead( ui64ReadOffset, uiBytesToRead, 
-			pvBuffer, FALSE, puiBytesRead);
+			pvBuffer, puiBytesRead);
 		goto Exit;
 	}
 
@@ -802,7 +800,7 @@ RCODE FLMAPI F_FileHdl::sectorRead(
 	if( m_bDoDirectIO)
 	{
 		return( directRead( ui64ReadOffset, uiBytesToRead, 
-			pvBuffer, TRUE, puiBytesRead));
+			pvBuffer, puiBytesRead));
 	}
 	else
 	{
@@ -933,10 +931,10 @@ RCODE FLMAPI F_FileHdl::write(
 	
 	f_assert( m_bFileOpened);
 
-	if( m_bDoDirectIO)
+	if( m_bDoDirectIO || m_bOpenedInAsyncMode)
 	{
 		rc = directWrite( ui64WriteOffset, uiBytesToWrite, pvBuffer, 
-			NULL, puiBytesWrittenRV, FALSE, TRUE);
+			NULL, puiBytesWrittenRV);
 		goto Exit;
 	}
 	
@@ -988,6 +986,7 @@ RCODE F_FileHdl::allocAlignedBuffer( void)
 	// boundary if it is not already on one.
 
 	m_uiAlignedBuffSize = (FLMUINT)roundUpToSectorMultiple( 64 * 1024);
+	f_assert( m_uiAlignedBuffSize >= m_uiBytesPerSector);
 	
 #if defined( FLM_SOLARIS)
 	if( (m_pucAlignedBuff = (FLMBYTE *)memalign( 
@@ -1021,9 +1020,7 @@ RCODE F_FileHdl::directWrite(
 	FLMUINT			uiBytesToWrite,
 	const void *	pvBuffer,
 	IF_IOBuffer *	pBufferObj,
-	FLMUINT *		puiBytesWrittenRV,
-	FLMBOOL			bBuffHasFullSectors,
-	FLMBOOL			bZeroFill)
+	FLMUINT *		puiBytesWrittenRV)
 {
 	RCODE				rc = NE_FLM_OK;
 	FLMUINT			uiBytesRead;
@@ -1060,12 +1057,9 @@ RCODE F_FileHdl::directWrite(
 	pucSrcBuffer = (FLMBYTE *)pvBuffer;
 	for (;;)
 	{
-		// See if we are using an aligned buffer.  If not, allocate
-		// one (if not already allocated), and use it.
-
 		if( (ui64WriteOffset & m_ui64NotOnSectorBoundMask) ||
-			 (((FLMUINT64)(FLMUINT)pucSrcBuffer) & m_ui64NotOnSectorBoundMask) ||
-			 ((uiBytesToWrite & m_ui64NotOnSectorBoundMask) && !bBuffHasFullSectors))
+			 (uiBytesToWrite & m_ui64NotOnSectorBoundMask) ||
+			 ((FLMUINT64)(FLMUINT)pucSrcBuffer) & m_ui64NotOnSectorBoundMask)
 		{
 			// Cannot do an async write if we have to use a temporary buffer
 			
@@ -1108,7 +1102,7 @@ RCODE F_FileHdl::directWrite(
 			// sector into the buffer.
 
 			if( (ui64WriteOffset & m_ui64NotOnSectorBoundMask) ||
-				(uiBytesBeingOutput < m_uiBytesPerSector && !bBuffHasFullSectors))
+				(uiBytesBeingOutput < m_uiBytesPerSector))
 			{
 				// Read the first sector that is to be written out.
 				// Read one sector's worth of data - so that we will
@@ -1137,15 +1131,9 @@ RCODE F_FileHdl::directWrite(
 		}
 		else
 		{
-			uiMaxBytesToWrite = (FLMUINT)roundUpToSectorMultiple( uiBytesToWrite);
-			uiBytesBeingOutput = uiBytesToWrite;
 			pucWriteBuffer = pucSrcBuffer;
-			
-			if( bZeroFill && uiMaxBytesToWrite > uiBytesToWrite)
-			{
-				f_memset( &pucWriteBuffer[ uiBytesToWrite], 0,
-							uiMaxBytesToWrite - uiBytesToWrite);
-			}
+			uiMaxBytesToWrite = uiBytesToWrite;
+			uiBytesBeingOutput = uiBytesToWrite;
 		}
 
 		// Position the file to the nearest sector below the write offset.
@@ -1153,7 +1141,7 @@ RCODE F_FileHdl::directWrite(
 		uiLastWriteOffset = (FLMUINT)getSectorStartOffset( ui64WriteOffset);
 		uiLastWriteSize = uiMaxBytesToWrite;
 		
-		if( bWaitForWrite)
+		if( !m_bOpenedInAsyncMode)
 		{
 			FLMINT		iBytesWritten;
 			
@@ -1173,7 +1161,18 @@ RCODE F_FileHdl::directWrite(
 #ifndef FLM_NLM
 		else
 		{
-			struct aiocb *		pAio = ((F_IOBuffer *)pBufferObj)->getAIOStruct();
+			struct aiocb *		pAio;
+			struct aiocb		tmpAio;
+			
+			if( pBufferObj)
+			{
+				pAio = ((F_IOBuffer *)pBufferObj)->getAIOStruct();
+			}
+			else
+			{
+				pAio = &tmpAio;
+				f_assert( bWaitForWrite);
+			}
 			
 			f_memset( pAio, 0, sizeof( struct aiocb));
 			pAio->aio_lio_opcode = LIO_WRITE;
@@ -1183,13 +1182,63 @@ RCODE F_FileHdl::directWrite(
 			pAio->aio_nbytes = uiMaxBytesToWrite;
 			pAio->aio_buf = pucWriteBuffer;
 			
-			if( aio_write( pAio) == -1)
+			if( aio_write( pAio) != 0)
 			{
+				f_assert( 0);
 				rc = f_mapPlatformError( errno, NE_FLM_WRITING_FILE);
 				goto Exit;
 			}
-			
-			pBufferObj->makePending();
+
+			if( bWaitForWrite)
+			{
+				struct aiocb *		ppAioList[ 1];
+				
+				ppAioList[ 0] = pAio;
+				
+				for( ;;)
+				{
+					FLMINT 	iAsyncResult;
+					
+					if( aio_suspend( ppAioList, 1, NULL) != 0)
+					{
+						if( errno == EINTR)
+						{
+							continue;
+						}
+						
+						f_assert( 0);
+						rc = f_mapPlatformError( errno, NE_FLM_WRITING_FILE);
+						goto Exit;
+					}
+					
+					iAsyncResult = aio_error( pAio);
+					
+					if( !iAsyncResult)
+					{
+						if( (iAsyncResult = aio_return( pAio)) < 0)
+						{
+							f_assert( 0);
+							rc = f_mapPlatformError( errno, NE_FLM_WRITING_FILE);
+							goto Exit;
+						}
+						
+						break;
+					}
+					
+					if( iAsyncResult == EINTR || iAsyncResult == EINPROGRESS)
+					{
+						continue;
+					}
+					
+					f_assert( 0);
+					rc = f_mapPlatformError( iAsyncResult, NE_FLM_WRITING_FILE);
+					goto Exit;
+				}
+			}
+			else
+			{
+				pBufferObj->makePending();
+			}
 		}
 #endif
 
@@ -1406,7 +1455,7 @@ FLMUINT f_getLinuxMaxFileSize( void)
 	
 	f_assert( gv_uiLinuxMajorVer);
 	
-	// Is version 2.4 or greater?
+	// Version 2.4 or greater?
 
 	if( gv_uiLinuxMajorVer > 2 || 
 		(gv_uiLinuxMajorVer == 2 && gv_uiLinuxMinorVer >= 4))
diff --git a/ftk/src/ftkwin.cpp b/ftk/src/ftkwin.cpp
index c9e555a..20bf152 100644
--- a/ftk/src/ftkwin.cpp
+++ b/ftk/src/ftkwin.cpp
@@ -612,7 +612,6 @@ RCODE F_FileHdl::directRead(
 	FLMUINT64		ui64ReadOffset,
 	FLMUINT			uiBytesToRead,
    void *			pvBuffer,
-	FLMBOOL			bBuffHasFullSectors,
    FLMUINT *		puiBytesReadRV)
 {
 	RCODE				rc = NE_FLM_OK;
@@ -646,8 +645,7 @@ RCODE F_FileHdl::directRead(
 
 		if ((ui64ReadOffset & m_ui64NotOnSectorBoundMask) ||
 			 (((FLMUINT64)pucDestBuffer) & m_ui64NotOnSectorBoundMask) ||
-			 (((FLMUINT64)uiBytesToRead & m_ui64NotOnSectorBoundMask) &&
-			  (!bBuffHasFullSectors)))
+			 (((FLMUINT64)uiBytesToRead & m_ui64NotOnSectorBoundMask)))
 		{
 			if (!m_pucAlignedBuff)
 			{
@@ -770,7 +768,7 @@ RCODE FLMAPI F_FileHdl::read(
 	if (m_bDoDirectIO)
 	{
 		rc = directRead( ui64ReadOffset, uiBytesToRead,
-									pvBuffer, FALSE, puiBytesReadRV);
+									pvBuffer, puiBytesReadRV);
 		goto Exit;
 	}
 
@@ -1084,27 +1082,25 @@ RCODE F_FileHdl::directWrite(
 	FLMUINT				uiBytesToWrite,
    const void *		pvBuffer,
 	IF_IOBuffer *		pBufferObj,
-	FLMBOOL				bBuffHasFullSectors,
-	FLMBOOL				bZeroFill,
    FLMUINT *			puiBytesWrittenRV)
 {
-	RCODE				rc = NE_FLM_OK;
-	FLMUINT			uiBytesRead;
-	FLMUINT			uiBytesWritten;
-	FLMBYTE *		pucWriteBuffer;
-	FLMBYTE *		pucSrcBuffer;
-	FLMUINT			uiMaxBytesToWrite;
-	FLMUINT64		ui64CurrFileSize;
-	FLMUINT			uiBytesBeingOutput;
-	OVERLAPPED *	pOverlapped;
-	DWORD				udErr;
-	FLMBOOL			bExtendFile = FALSE;
-	FLMBOOL			bWaitForWrite = (pBufferObj == NULL)
+	RCODE					rc = NE_FLM_OK;
+	FLMUINT				uiBytesRead;
+	FLMUINT				uiBytesWritten;
+	FLMBYTE *			pucWriteBuffer;
+	FLMBYTE *			pucSrcBuffer;
+	FLMUINT				uiMaxBytesToWrite;
+	FLMUINT64			ui64CurrFileSize;
+	FLMUINT				uiBytesBeingOutput;
+	OVERLAPPED *		pOverlapped;
+	DWORD					udErr;
+	FLMBOOL				bExtendFile = FALSE;
+	FLMBOOL				bWaitForWrite = (pBufferObj == NULL)
 										? TRUE
 										: FALSE;
-	FLMUINT64		ui64LastWriteOffset;
-	FLMUINT			uiLastWriteSize;
-	LARGE_INTEGER	liTmp;
+	FLMUINT64			ui64LastWriteOffset;
+	FLMUINT				uiLastWriteSize;
+	LARGE_INTEGER		liTmp;
 
 	f_assert( m_bFileOpened);
 
@@ -1168,8 +1164,7 @@ RCODE F_FileHdl::directWrite(
 
 		if ((ui64WriteOffset & m_ui64NotOnSectorBoundMask) ||
 			 (((FLMUINT)pucSrcBuffer) & m_ui64NotOnSectorBoundMask) ||
-			 ((uiBytesToWrite & m_ui64NotOnSectorBoundMask) &&
-			  (!bBuffHasFullSectors)))
+			 (uiBytesToWrite & m_ui64NotOnSectorBoundMask))
 		{
 
 			// Cannot do an async write if we have to use a temporary buffer
@@ -1231,8 +1226,7 @@ RCODE F_FileHdl::directWrite(
 			// we must read in this sector as well.
 
 			if ((uiMaxBytesToWrite > m_uiBytesPerSector) &&
-				 (uiMaxBytesToWrite > uiBytesToWrite) &&
-				 (!bBuffHasFullSectors))
+				 (uiMaxBytesToWrite > uiBytesToWrite))
 			{
 
 				// Read the last sector that is to be written out.
@@ -1268,14 +1262,9 @@ RCODE F_FileHdl::directWrite(
 		}
 		else
 		{
-			uiMaxBytesToWrite = roundToNextSector( uiBytesToWrite);
-			uiBytesBeingOutput = uiBytesToWrite;
 			pucWriteBuffer = pucSrcBuffer;
-			if( bZeroFill && uiMaxBytesToWrite > uiBytesToWrite)
-			{
-				f_memset( &pucWriteBuffer [uiBytesToWrite], 0,
-							uiMaxBytesToWrite - uiBytesToWrite);
-			}
+			uiMaxBytesToWrite = uiBytesToWrite;
+			uiBytesBeingOutput = uiBytesToWrite;
 		}
 
 		// Position the file to the nearest sector below the write offset.
@@ -1433,7 +1422,7 @@ RCODE FLMAPI F_FileHdl::write(
 	if (m_bDoDirectIO)
 	{
 		rc = directWrite( ui64WriteOffset, uiBytesToWrite, pvBuffer,
-								NULL, FALSE, FALSE, puiBytesWrittenRV);
+								NULL, puiBytesWrittenRV);
 		goto Exit;
 	}