diff --git a/include/libxml/trionan.h b/include/libxml/trionan.h
new file mode 100644
index 0000000..f955198
--- /dev/null
+++ b/include/libxml/trionan.h
@@ -0,0 +1,54 @@
+/*************************************************************************
+ *
+ * $Id$
+ *
+ * Copyright (C) 2001 Bjorn Reese <breese@users.sourceforge.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND
+ * CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER.
+ *
+ ************************************************************************/
+
+#ifndef __TRIO_NAN_H__
+#define __TRIO_NAN_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Return NaN (Not-a-Number).
+ */
+double trio_nan(void);
+
+/*
+ * Return positive infinity.
+ */
+double trio_pinf(void);
+
+/*
+ * Return negative infinity.
+ */
+double trio_ninf(void);
+  
+/*
+ * If number is a NaN return non-zero, otherwise return zero.
+ */
+int trio_isnan(double number);
+
+/*
+ * If number is positive infinity return 1, if number is negative
+ * infinity return -1, otherwise return 0.
+ */
+int trio_isinf(double number);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __TRIO_NAN_H__ */