atol supports trailing l/L if base is 0
diff --git a/Doc/lib/libstring.tex b/Doc/lib/libstring.tex
index ac6dc55..2e79d43 100644
--- a/Doc/lib/libstring.tex
+++ b/Doc/lib/libstring.tex
@@ -79,7 +79,7 @@
 string must consist of one or more digits, optionally preceded by a
 sign (\samp{+} or \samp{-}).  The \var{base} argument has the same
 meaning as for \code{atoi()}.  A trailing \samp{l} or \samp{L} is not
-allowed.
+allowed, except if the base is 0.
 \end{funcdesc}
 
 \begin{funcdesc}{expandtabs}{s\, tabsize}