## Code
\documentclass[tikz,convert=false]{standalone}
\makeatletter
\newif\iftikz@ortho@preflush
\tikz@ortho@preflushtrue
\let\tikz@origtotarget\pgfutil@empty
\tikzset{
|-/.style={to path={|- (\tikztotarget) \tikztonodes}},
-|/.style={to path={-| (\tikztotarget) \tikztonodes}},
*|/.style={to path={%
\pgfextra
\iftikz@shapeborder
\tikz@scan@one@point\pgfutil@firstofone(\tikztotarget)\relax
\ifdim\pgf@y>\tikz@lasty\relax
\edef\tikztostart{\tikztostart.north}%
\else
\edef\tikztostart{\tikztostart.south}%
\fi
\fi
\endpgfextra
(\tikztostart-|\tikztotarget) -- (\tikztotarget) \tikztonodes
}},
*-/.style={to path={%
\pgfextra
\iftikz@shapeborder
\tikz@scan@one@point\pgfutil@firstofone(\tikztotarget)\relax
\ifdim\pgf@x>\tikz@lastx\relax
\edef\tikztostart{\tikztostart.east}%
\else
\edef\tikztostart{\tikztostart.west}%
\fi
\fi
\endpgfextra
(\tikztostart|-\tikztotarget) -- (\tikztotarget) \tikztonodes
}},
|*/.style={to path={%
\pgfextra
\tikz@scan@one@point\pgfutil@firstofone(\tikztotarget)\relax
\iftikz@shapeborder
\let\tikz@origtotarget\tikztotarget
\ifdim\pgf@y>\tikz@lasty\relax
\edef\tikztotarget{\tikztotarget.south}%
\else
\edef\tikztotarget{\tikztotarget.north}%
\fi
\fi
\endpgfextra
(\tikztostart) -- (\tikztostart|-\tikztotarget) \tikztonodes
\tikztonodes \ifx\tikz@origtotarget\pgfutil@empty\else\iftikz@ortho@preflush(\tikz@origtotarget)\fi\fi
}},
-*/.style={to path={%
\pgfextra
\tikz@scan@one@point\pgfutil@firstofone(\tikztotarget)\relax
\iftikz@shapeborder
\let\tikz@origtotarget\tikztotarget
\ifdim\pgf@x>\tikz@lastx\relax
\edef\tikztotarget{\tikztotarget.west}%
\else
\edef\tikztotarget{\tikztotarget.east}%
\fi
\fi
\endpgfextra
(\tikztostart) -- (\tikztostart-|\tikztotarget) \tikztonodes
}}}
\tikztonodes \ifx\tikz@origtotarget\pgfutil@empty\else\iftikz@ortho@preflush(\tikz@origtotarget)\fi\fi
}},
node as new start/.is if=tikz@ortho@preflush
}
\makeatother
\begin{document}
\begin{tikzpicture}
\begin{scope}[nodes={shape=rectangle, draw, minimum width=+1.5cm, minimum height=+1cm}]
\node (a) {A};
\node (b) at ( .5, 2 ) {B};
\node (c) at ( 2.5,- .2) {C};
\node (d) at (- .5,-2 ) {D};
\node (e) at (-2.5, .2) {E};
\end{scope}
\tikzset{nodes={auto,font=\small\ttfamily}}
\path[->] (a) edge[*|] (b)
(b) edge[*|] node {*|} (a)
(a) edge[*-] (c)
(c) edge[*-] node[swap] {*-} (a)
(a) edge[|*] (d)
(d) edge[|*] node[swap] {|*} (a)
(a) edge[-*] (e)
(e) edge[-*] node {-*} (a)
%
{[every edge/.append style=blue]
{[|-]
(e) edge (b)
edge (d)}
{[-|]
(b) edge (c)
(d) edge (c)}}
;
\end{tikzpicture}
\begin{tikzpicture}[nodes={shape=rectangle, draw, minimum width=+1cm, minimum height=+1cm}]
\node (a) {A};
\node (b) at ( .25, 2) {B};
\node (c) at (1.25,-0) {C};
\draw (a) to [|*] (b) to (c);
\begin{scope}[xshift=3cm, node as new start=false]
\node (a) {A};
\node (b) at ( .25, 2) {B};
\node (c) at (1.25,-0) {C};
\draw (a) to [|*] (b) to (c);
\end{scope}
\end{tikzpicture}
\begin{tikzpicture}[nodes={rectangle,draw,anchor=west,minimum height=+1cm}]
\node (rechteck1)[minimum width=+3cm] at (1,5){};
\node (rechteck2)[minimum width=+2cm] at (1,3){};
\draw [->] (rechteck1) to[*|] (rechteck2);
\end{tikzpicture}
\end{document}
## Resultat
![alt text][1]
![alt text][2]
![alt text][3]
[1]: http://texwelt.de/wissen/upfiles/de1289-0.png
[2]: http://texwelt.de/wissen/upfiles/de1289-1_1.png
[3]: http://texwelt.de/wissen/upfiles/de1289-1.png
