diff --git a/include/compat.h b/include/compat.h
new file mode 100644
index 00000000..69498954
--- /dev/null
+++ b/include/compat.h
@@ -0,0 +1,48 @@
+/*
+ * $Id:$
+ *
+ * compat.h - Tweaks for Windows compatability
+ *
+ * Copyright (c) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _NTFS_COMPAT_H
+#define _NTFS_COMPAT_H
+
+#ifdef WINDOWS
+
+extern int ffs (int i);
+
+#define HAVE_STDIO_H		/* mimic config.h */
+#define HAVE_STDARG_H
+
+#define atoll			_atoi64
+#define fdatasync		commit
+#define __inline__		inline
+#define __attribute__(X)	/*nothing*/
+
+#else /* !defined WINDOWS */
+
+#ifndef O_BINARY
+#define O_BINARY		0		/* unix is binary by default */
+#endif
+
+#endif /* defined WINDOWS */
+
+#endif /* defined _NTFS_COMPAT_H */
+
diff --git a/libntfs/compat.c b/libntfs/compat.c
new file mode 100644
index 00000000..c4d7ae94
--- /dev/null
+++ b/libntfs/compat.c
@@ -0,0 +1,58 @@
+/*
+ * $Id$
+ *
+ * compat.c - Tweaks for Windows compatability
+ *
+ * Copyright (c) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifdef WINDOWS
+
+#include "compat.h"
+
+int ffs (int x)
+{
+	int r = 1;
+
+	if (!x)
+		return 0;
+	if (!(x & 0xffff)) {
+		x >>= 16;
+		r += 16;
+	}
+	if (!(x & 0xff)) {
+		x >>= 8;
+		r += 8;
+	}
+	if (!(x & 0xf)) {
+		x >>= 4;
+		r += 4;
+	}
+	if (!(x & 3)) {
+		x >>= 2;
+		r += 2;
+	}
+	if (!(x & 1)) {
+		x >>= 1;
+		r += 1;
+	}
+	return r;
+}
+
+#endif /* WINDOWS */
+