# Unison preferences for syncing

Unison is a tool to compare and synchronize two folders. You can configure it by GUI, but at least for me (Kubuntu 18.04) not all settings work. Specifically, I cannot set the value “0”. But there is an easy way around the problem. Unison puts a file called Profilename.prf (where “Profilename” should be replaced with the actual name of your profile) into the folder .unison in your home directory. This is simply a text file with key-value pairs, that you can edit at your leisure.

Here are standard settings for comparing two directories without comparing the file permissions:

label = My first comparison
root = /home/test/FolderOne/
root = /home/test/FolderTwo/
perms = 0
dontchmod = true


Now for the coolest feature of Unison: It is written in OCaml!! OCaml was used in my third semester to teach functional programming. I remember clearly the teacher telling us about the “usefulness” of the language. She had one slide with examples of programs written in OCaml. And she must have looked very hard to find any. There were a grand total of three programs on the slide. Two formal logic resolvers or something to that effect (we were like “yeah, really useful”). And MLDonkey (peer-to-peer filesharing was BIG in those days before Netflix, Spotify and fast internet) which she clearly didn’t know what it was for. So now, if she still has that slide, I can add another program! And a really useful one at that!

# Typearea settings for a scrbook

Here are dirty hacks for page layout in LaTeX and a few useful standard settings.

I load the following document class:

\documentclass[bibliography=totoc,12pt,a4paper,headsepline]{scrbook}


The option bibliography=totoc puts the bibliography into table of contents. The option 12pt sets normal font size to 12pt instead of the usual 11pt. This font size was a requirement for my thesis. The option a4paper sets DIN A4 paper (which should be the default anyway). The option headsepline adds a line below the header content on pages without a title.

A useful additional option may be oneside, which creates symmetric margins for one-sided print. Again, that was a requirement for the manuscript of my thesis. For the final print, I needed a normal two-sided print. A useful option there is titlepage=firstiscover, which gives equal margins for the first two pages (the book cover).

Usually you don’t want to tamper with the margins that LaTeX gives you. But in some cases, you may have specific guidelines that you need to adhere to. Or you have a fixed number of pages and run out of space, so you want smaller margins. Anyway, this is not recommended, I am just showing you how it works, because I can.

We have loaded the documentclass scrbook which is the KOMA-Script document class for an DIN A4 page book with a font size of 12pt. At that paper and font size, KOMA-Script uses a value of DIV=12 to calculate margins and text area sizes. The page has a width of 157.50mm and a height of 222.75mm for the text area. The top margin is 24.75mm and the inner margin 17.50mm. You can increase or decrease the margins by setting a different DIV value. So if you use the option DIV=13 for example, you will have a bigger text area (161mm wide instead of only 157mm). You can play around with the values until you find something you like. Here are the measurements for different DIV values for an DIN A4 page:

If you don’t find anything you like, you can set all values by hand with the geometry package. Use at your own peril. This is an example with a larger text height:

\usepackage[width=157.50mm,top=35mm,left=24mm]{geometry}  % gives textheight=226.36mm


When you play around with margins and text area settings, the package showframe is useful to see what you are doing:

\usepackage{showframe}


# “Non-sciency” table-of-contents in a LaTeX book

One of my “customers” wanted a book that didn’t look so “sciency” (i.e., like LaTeX). In addition to the look of the chapter and sections headings (described in my last post), my “customers” wanted the table-of-contents to also look “non-sciency”. So this is what I did.

The package to use for manipulations of the table-of-contents is titletoc:

\usepackage{titletoc}


The entry for a chapter specifies that chapters are prefaced with the chapter label (which is “Teil X” in our case) and otherwise pretty standard:

\titlecontents{chapter}
[3.2em] % left margin from the left page margin. % default 1.5em
{\addvspace{1em}\usekomafont{title}} % global formatting of the entry.
{\contentslabel{3.2em}}  % numbered entry
{\hspace*{-1.3em}} % non-nubered entry
{\titlerule*[.5pc]{}\contentspage}  % filler-page format


Sections are not numbered and otherwise rather standard, except for a few adjustments of spacing:

\titlecontents{section}
[1em] % left margin from the left page margin.
{} % global formatting of the entry.
{} % numbered entry, default \contentslabel{2.3em}
{} % non-nubered entry
{~\titlerule*[.7pc]{.}\contentspage} % filler-page format


# “Non-sciency” chapters and sections in a LaTeX book

One of my “customers” wanted a book that didn’t look so “sciency” (i.e., less like LaTeX). The first few tweaks (described in my last post) were more general, this one deals with the look of chapter and section headings.

I use the package titlesec for the task:

\usepackage{titlesec}


Each chapter should start on its own page. On top it will say “Teil X”, then a line, then the chapter name centered. At the bottom of the page a picture is included. This is the code for it:

\titleformat{\chapter} % command
[display] % shape: display, block, runin, hang (default)
{\bfseries\Large\itshape} % format
{\thechapter} % label
{0.5ex} % sep btw. label and title body
{\rule{\textwidth}{1pt} \vspace{1ex} \centering} % before-code
[{\vfill\includegraphics[width=\linewidth]{\Chapterimg}\pagebreak}] % after-code


The image for a chapter is set before each chapter with the custom-defined command Chapterimg:

\def\Chapterimg{img/chapterimage6}
\chapter{Einleitung}


A section is just the title in large bold font, no number in front of it:

\titleformat{\section} % command
[block] % shape
{\usekomafont{title}\large} % format
{}  % label
{0pt} % sep
{} % before-code
[] % after-code


I also adjusted the spacing a bit:

\titlespacing{\section}{0pt}{1ex}{0pt} % less space for sections
\titlespacing{\subsection}{0pt}{0pt}{0pt} % subsection is like a paragraph


In a previous version of the book, the images were supposed to be placed next to the section headings. My attempt at doing that was to include the image in the “after-code” of the section format and add a bit of space at the right margin for it. It looked ok, but there were some issues with one-line vs. multi-line titles that I didn’t fix, because the images moved to the chapters instead.

[{\vspace{-3em}\hfill\includegraphics[width=4em]{\Chapterimg}\hspace{-5em}~}] % after-code
\titlespacing{\section}{0pt}{1ex}{0pt}[6em] % left margin / before / after / [right]