%% 
%%  A DANTE-Edition example
%% 
%%  Example 04-01-1 on page 126.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{225.70511pt}
\setlength\parindent{0pt}
\setlength\textwidth{220pt}

\usepackage{longtable}

\begin{document}
left \hfill centred \hfill right

\begin{longtable}{|l|c|r|p{1.7cm}|}\hline
left & centred & right & box\\\hline
l & c & r & p\{1.7cm\}\\\hline
\end{longtable}
% right-aligned
\begin{longtable}[r]{|l|c|r|p{1.7cm}|}\hline
left & centred & right & box\\\hline
l & c & r & p\{1.7cm\}\\\hline
\end{longtable}
% left-aligned
\begin{longtable}[l]{|l|c|r|p{1.7cm}|}\hline
left & centred & right & box\\\hline
l & c & r & p\{1.7cm\}\\\hline
\end{longtable}
\end{document}