Note that unicode() can raise LookupError for unknown codecs.
Closes SF bug #513666.
diff --git a/Doc/lib/libfuncs.tex b/Doc/lib/libfuncs.tex
index f695c3d..5526dc5 100644
--- a/Doc/lib/libfuncs.tex
+++ b/Doc/lib/libfuncs.tex
@@ -859,7 +859,8 @@
If \var{encoding} and/or \var{errors} are given, \code{unicode()}
will decode the object which can either be an 8-bit string or a
character buffer using the codec for \var{encoding}. The
- \var{encoding} parameter is a string giving the name of an encoding.
+ \var{encoding} parameter is a string giving the name of an encoding;
+ if the encoding is not known, \exception{LookupError} is raised.
Error handling is done according to \var{errors}; this specifies the
treatment of characters which are invalid in the input encoding. If
\var{errors} is \code{'strict'} (the default), a