\documentclass[english,a4paper,twoside,openright]{report}

  \usepackage[utf8]{inputenc}
  \usepackage{graphicx}
	\usepackage{url}

	\usepackage{makeidx}
	\makeindex

  \setlength{\parindent}{0em}
  \setlength{\parskip}{1.0ex plus 1.0ex minus 0.5ex}
  \setcounter{tocdepth}{3}

  \pagestyle{headings}
  %\pagestyle{fancy}
	%\lhead[\leftmark]{\thepage}
	%\chead[]{}
	%\rhead[\thepage]{\rightmark}
  %\ifoot[\textsc{Markus Schnalke}]{\textsc{Markus Schnalke}}
  %\cfoot[]{}
  %\ofoot[\thepage]{\thepage}

	\usepackage{setspace}
	\usepackage{relsize}

	% formating
  \renewcommand{\path}[1]{\textit{#1}}
  \newcommand{\name}[1]{\emph{#1}}
	\newcommand{\NAME}[1]{{\smaller\textsc{#1}\larger}}

  % \newcommand{\source}[1]{\hspace{1em}\textit{\scriptsize(Quelle: #1)}}
	\let\OLDcleardoublepage\cleardoublepage
	\renewcommand{\cleardoublepage}{\thispagestyle{empty}\OLDcleardoublepage}

	% shortcuts
	\newcommand{\masqmail}{\name{masqmail}}
	\newcommand{\sendmail}{\name{sendmail}}
	\newcommand{\mta}{\name{mail transfer agent}}
	\newcommand{\email}{\name{email}}
	\newcommand{\debian}{\name{Debian}}
	\newcommand{\linux}{\name{Linux}}
	\newcommand{\gnulinux}{\NAME{GNU}/\name{Linux}}
	\newcommand{\MTA}{\NAME{MTA}}
	\newcommand{\RFC}{\NAME{RFC}}
	\newcommand{\GNU}{\NAME{GNU}}

	%%%% BEGIN DEBUG %%%%
	%\usepackage{showidx}
	%\doublespace
	%%%% END DEBUG %%%%


	% font
	\usepackage[T1]{fontenc}
	\usepackage[sc,osf]{mathpazo}
	\linespread{1.05}         % Palatino needs more leading (space between lines)



  \usepackage{listings}
	\lstset{
		basicstyle=\ttfamily\footnotesize,
		numberstyle=\tiny,
		basewidth=0.45em,
		numbers=left,
		stepnumber=1,
		numbersep=2em,
		showstringspaces=true,
		showtabs=true,
		tab=\rightarrowfill,
		frame=lines,
		tabsize=4,
		captionpos=b,
		breaklines=false,
		breakatwhitespace=true
	}


	\newenvironment{code}[2] {
		\begin{center}
		\lstset{label=#1,caption=#2}
		\begin{list}{}{\setlength{\rightmargin}{2em}\setlength{\leftmargin}{2em}}
		\item\ttfamily\footnotesize
	}{
		\end{list}
		\end{center}
	}