[Tex/LaTex] Twosided book with same page setup for every page (I want to use fancyhdr)

double-sidedfancyhdrgeometryheader-footermargins

Here is my problem:

Im writing my thesis using the book class. I want my thesis to be onesided (left and right margins of same size), but I would also like to use the fancyhdr package to give me chapter names in the pagehead of even pages and section names in the pagehead of odd pages.

Trying to do so together with the "oneside" option gives me a warning when compiling saying that the [E] option is useless when the book is "onesided".

Example code:

\documentclass[11pt,a4paper, oneside]{book}
...
\fancyhf{} 
\pagestyle{fancy}
\headheight 20pt
\fancyhead[LE]{\rightmark}

Any good ideas would be much appreciated!
I already tried the geometry package, and it messes up a lot of the formatting in the book class.
I guess what I'm basically looking for is how to use the "twosided" option without LaTeX shifting every other page to a side.

Best Answer

I also recommend using the geometry package. However, if you insist on not "messing up" any formatting, you may temporarily enable the oneside class option, then use the \showthe command to find out the value of the lengths \evensidemargin (and \oddsidemargin) with this option, then switch back to twoside and change the two length values.

\documentclass{book}% Defaults to [twoside]

% \showthe\evensidemargin% Retrieve length value with class option [oneside]

% Apply length value of class option [oneside]
\evensidemargin 62pt
\oddsidemargin 62pt

\usepackage{fancyhdr}
\pagestyle{fancy}

\usepackage{blindtext}

\begin{document}

\blinddocument

\end{document}

(The blindtext package is only used to add some dummy text to the example.)