fix wording

Author: Vladimir Kotal

user-access.tex

@@ -404,7 +404,7 @@
 \end{slide}
 
 \begin{itemize}
-\item The \texttt{getuid} returns real the UID, there is nothing like
+\item The \texttt{getuid} returns the real UID, there is nothing like
 \texttt{getruid}.
 \item \texttt{getgroups}: when \texttt{gidsz~==~0}, it returns the number of
 groups. When \texttt{0 < gidsz < \#groups}, it returns \texttt{-1}.