Added note about non-support of UNC paths on Windows.
This fixes SF bug #465447.
diff --git a/Doc/lib/libposixpath.tex b/Doc/lib/libposixpath.tex
index 9cd1a58..bc26ddd 100644
--- a/Doc/lib/libposixpath.tex
+++ b/Doc/lib/libposixpath.tex
@@ -7,6 +7,10 @@
 This module implements some useful functions on pathnames.
 \index{path!operations}
 
+\strong{Warning:}  On Windows, many of these functions do not properly
+support UNC pathnames.  \function{splitunc()} and \function{ismount()}
+do handle them correctly.
+
 
 \begin{funcdesc}{abspath}{path}
 Return a normalized absolutized version of the pathname \var{path}.