\documentclass{article}
\usepackage{tabulary}
\setlength\tymin{10pt}
\setlength\tymax{\maxdimen}
\usepackage{bidi}
\title{Testing \textsf{tabulary} package in RTL and LTR}
\author{Vafa Khalighi}
\begin{document}
\maketitle
\section{LTR}
\begin{tabulary}{200pt}{|C|C|C|C|}
 a & b b b b &
 c c c c c c c c c c c c c c c c c c &
 d d d d d d d d d d d d d d d d d d
\empty
 d d d d d d d d d d d d d d
 d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d
 \end{tabulary}
\section{RTL}

\setRTL
\begin{tabulary}{200pt}{|C|C|C|C|}
 a & b b b b &
 c c c c c c c c c c c c c c c c c c &
 d d d d d d d d d d d d d d d d d d
\empty
 d d d d d d d d d d d d d d
 d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d
 \end{tabulary}
\end{document}
