diff --git a/examples/20150504/Makefile b/examples/20150504/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..0db34c8b628fad5594dcc293e50222390cfa9096
--- /dev/null
+++ b/examples/20150504/Makefile
@@ -0,0 +1,7 @@
+obj-m += chardev.o
+
+all:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+
+clean:
+ make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
diff --git a/examples/20150504/chardev.c b/examples/20150504/chardev.c
new file mode 100644
index 0000000000000000000000000000000000000000..17a6651a33313322de202fbcb6bbf82333c0b766
--- /dev/null
+++ b/examples/20150504/chardev.c
@@ -0,0 +1,166 @@
+/*
+ * chardev.c: Creates a read-only char device that says how many times
+ * you've read from the dev file
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h> /* for put_user */
+
+/*
+ * Prototypes - this would normally go in a .h file
+ */
+int init_module(void);
+void cleanup_module(void);
+static int device_open(struct inode *, struct file *);
+static int device_release(struct inode *, struct file *);
+static ssize_t device_read(struct file *, char *, size_t, loff_t *);
+static ssize_t device_write(struct file *, const char *, size_t, loff_t *);
+
+#define SUCCESS 0
+#define DEVICE_NAME "chardev" /* Dev name as it appears in /proc/devices */
+#define BUF_LEN 80 /* Max length of the message from the device */
+
+/*
+ * Global variables are declared as static, so are global within the file.
+ */
+
+static int Major; /* Major number assigned to our device driver */
+static int Device_Open = 0; /* Is device open?
+ * Used to prevent multiple access to device */
+static char msg[BUF_LEN]; /* The msg the device will give when asked */
+static char *msg_Ptr;
+
+static struct file_operations fops = {
+ .read = device_read,
+ .write = device_write,
+ .open = device_open,
+ .release = device_release
+};
+
+/*
+ * This function is called when the module is loaded
+ */
+int init_module(void)
+{
+ Major = register_chrdev(0, DEVICE_NAME, &fops);
+
+ if (Major < 0) {
+ printk(KERN_ALERT "Registering char device failed with %d\n", Major);
+ return Major;
+ }
+
+ printk(KERN_INFO "I was assigned major number %d. To talk to\n", Major);
+ printk(KERN_INFO "the driver, create a dev file with\n");
+ printk(KERN_INFO "'mknod /dev/%s c %d 0'.\n", DEVICE_NAME, Major);
+ printk(KERN_INFO "Try various minor numbers. Try to cat and echo to\n");
+ printk(KERN_INFO "the device file.\n");
+ printk(KERN_INFO "Remove the device file and module when done.\n");
+
+ return SUCCESS;
+}
+
+/*
+ * This function is called when the module is unloaded
+ */
+void cleanup_module(void)
+{
+ /*
+ * Unregister the device
+ */
+ unregister_chrdev(Major, DEVICE_NAME);
+}
+
+/*
+ * Methods
+ */
+
+/*
+ * Called when a process tries to open the device file, like
+ * "cat /dev/mycharfile"
+ */
+static int device_open(struct inode *inode, struct file *file)
+{
+ static int counter = 0;
+
+ if (Device_Open)
+ return -EBUSY;
+
+ Device_Open++;
+ sprintf(msg, "I already told you %d times Hello world!\n", counter++);
+ msg_Ptr = msg;
+ try_module_get(THIS_MODULE);
+
+ return SUCCESS;
+}
+
+/*
+ * Called when a process closes the device file.
+ */
+static int device_release(struct inode *inode, struct file *file)
+{
+ Device_Open--; /* We're now ready for our next caller */
+
+ /*
+ * Decrement the usage count, or else once you opened the file, you'll
+ * never get get rid of the module.
+ */
+ module_put(THIS_MODULE);
+
+ return 0;
+}
+
+/*
+ * Called when a process, which already opened the dev file, attempts to
+ * read from it.
+ */
+static ssize_t device_read(struct file *filp, /* see include/linux/fs.h */
+ char *buffer, /* buffer to fill with data */
+ size_t length, /* length of the buffer */
+ loff_t * offset)
+{
+ /*
+ * Number of bytes actually written to the buffer
+ */
+ int bytes_read = 0;
+
+ /*
+ * If we're at the end of the message,
+ * return 0 signifying end of file
+ */
+ if (*msg_Ptr == 0)
+ return 0;
+
+ /*
+ * Actually put the data into the buffer
+ */
+ while (length && *msg_Ptr) {
+
+ /*
+ * The buffer is in the user data segment, not the kernel
+ * segment so "*" assignment won't work. We have to use
+ * put_user which copies data from the kernel data segment to
+ * the user data segment.
+ */
+ put_user(*(msg_Ptr++), buffer++);
+
+ length--;
+ bytes_read++;
+ }
+
+ /*
+ * Most read functions return the number of bytes put into the buffer
+ */
+ return bytes_read;
+}
+
+/*
+ * Called when a process writes to dev file: echo "hi" > /dev/hello
+ */
+static ssize_t
+device_write(struct file *filp, const char *buff, size_t len, loff_t * off)
+{
+ printk(KERN_ALERT "Sorry, this operation isn't supported.\n");
+ return -EINVAL;
+}
diff --git a/examples/20150504/hello.c b/examples/20150504/hello.c
new file mode 100644
index 0000000000000000000000000000000000000000..b19d80e9bd0bd7c5ed8f54b20c6a50d9166f03ac
--- /dev/null
+++ b/examples/20150504/hello.c
@@ -0,0 +1,7 @@
+#include <stdio.h>
+
+int main (void)
+{
+ printf ("Hello, world!\n");
+ return 0;
+}
diff --git a/examples/20150504/modhello-1.c b/examples/20150504/modhello-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..03ca857c833083669c88dc58707e4e434fbbc440
--- /dev/null
+++ b/examples/20150504/modhello-1.c
@@ -0,0 +1,20 @@
+/*
+ * modhello-1.c - The simplest kernel module.
+ */
+#include <linux/module.h> /* Needed by all modules */
+#include <linux/kernel.h> /* Needed for KERN_INFO */
+
+int init_module(void)
+{
+ printk(KERN_INFO "Hello, world!\n");
+
+ /*
+ * A non 0 return means init_module failed; module can't be loaded.
+ */
+ return 0;
+}
+
+void cleanup_module(void)
+{
+ printk(KERN_INFO "Goodbye, world!\n");
+}
diff --git a/examples/20150504/modhello-2.c b/examples/20150504/modhello-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..4014b4a0fc68580b6d949c024a21d5b5a0c4f785
--- /dev/null
+++ b/examples/20150504/modhello-2.c
@@ -0,0 +1,21 @@
+/*
+ * modhello-2.c - Demonstrating the module_init() and module_exit() macros.
+ * This is preferred over using init_module() and cleanup_module().
+ */
+#include <linux/module.h> /* Needed by all modules */
+#include <linux/kernel.h> /* Needed for KERN_INFO */
+#include <linux/init.h> /* Needed for the macros */
+
+static int __init hello_2_init(void)
+{
+ printk(KERN_INFO "Hello, world!\n");
+ return 0;
+}
+
+static void __exit hello_2_exit(void)
+{
+ printk(KERN_INFO "Goodbye, world!\n");
+}
+
+module_init(hello_2_init);
+module_exit(hello_2_exit);
diff --git a/slides/os-layers-1.jpg b/slides/os-layers-1.jpg
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diff --git a/src/logo-hochschule-bochum-cvh-text.pdf b/src/logo-hochschule-bochum-cvh-text.pdf
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diff --git a/src/pgslides.sty b/src/pgslides.sty
new file mode 100644
index 0000000000000000000000000000000000000000..ba8c0f9818fbb1467c288a871600b40191e5cc7f
--- /dev/null
+++ b/src/pgslides.sty
@@ -0,0 +1,168 @@
+% pgslides.sty - LaTeX Settings for Lecture Slides
+% Copyright (C) 2012, 2013 Peter Gerwinski
+%
+% This document is free software: you can redistribute it and/or
+% modify it either under the terms of the Creative Commons
+% Attribution-ShareAlike 3.0 License, or under the terms of the
+% GNU General Public License as published by the Free Software
+% Foundation, either version 3 of the License, or (at your option)
+% any later version.
+%
+% This document is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with this document. If not, see <http://www.gnu.org/licenses/>.
+%
+% You should have received a copy of the Creative Commons
+% Attribution-ShareAlike 3.0 Unported License along with this
+% document. If not, see <http://creativecommons.org/licenses/>.
+
+\usepackage[latin1]{inputenc}
+\usepackage[german]{babel}
+\usepackage[T1]{fontenc}
+\usepackage{helvet}
+\renewcommand*\familydefault{\sfdefault}
+
+\usetheme{default}
+\usefonttheme{structurebold}
+\setbeamertemplate{navigation symbols}{}
+\setbeamersize{text margin left = 0.3cm, text margin right = 0.2cm}
+\setbeamertemplate{itemize item}{$\bullet$}
+\setbeamertemplate{itemize subitem}{--}
+\setbeamerfont{itemize/enumerate subbody}{size=\normalsize}
+\setbeamerfont{itemize/enumerate subsubbody}{size=\normalsize}
+\setbeamercolor{footline}{fg=gray}
+
+\newcommand{\sep}{~$\cdot$~}
+
+\institute[Hochschule Bochum\sep CVH]{%
+ \makebox(0,0)[tl]{\includegraphics[scale=0.57]{logo-hochschule-bochum-cvh-text.pdf}}\hfill
+ \makebox(0,0)[tr]{\includegraphics[scale=0.5]{logo-hochschule-bochum.pdf}}%
+}
+
+\iffalse
+ \setbeamertemplate{footline}{}
+\else
+ \setbeamertemplate{footline}{%
+ \leavevmode%
+ \hbox to \textwidth{%
+ \usebeamercolor{footline}%
+ \usebeamerfont{footline}%
+ \iftrue
+ \strut\hfill
+ \else
+ \,\insertshorttitle\sep
+ \insertshortauthor\sep
+ \insertshortinstitute\sep
+ \insertshortdate\hfill
+ \fi
+ Folie\,\insertframenumber\sep Seite\,\insertpagenumber\,
+ }%
+ \vskip0pt%
+ }
+\fi
+
+\newcommand{\maketitleframe}{%
+ \begin{frame}[t,plain]
+ \insertinstitute
+ \par\vfill
+ \begin{center}
+ {\LARGE\color{structure}\inserttitle}\\[2\bigskipamount]
+ {\large \insertauthor}\\[1.5\bigskipamount]
+ \insertdate
+ \end{center}
+ \end{frame}
+}
+
+\usepackage{pstricks}
+\newrgbcolor{lightyellow}{0.95 0.85 0.0}
+\newrgbcolor{lightorange}{1.0 0.7 0.0}
+\newrgbcolor{lightgreen}{0.0 0.8 0.0}
+\newrgbcolor{medgreen}{0.0 0.5 0.0}
+\newrgbcolor{darkgreen}{0.0 0.3 0.0}
+\newrgbcolor{lightred}{1.0 0.7 0.7}
+\newrgbcolor{lightgray}{0.85 0.85 0.85}
+\definecolor{darkgray}{rgb}{0.4,0.4,0.4}
+
+\newenvironment{experts}{\color{darkgray}}{}
+\catcode`\_=13\def_{\kern1pt\rule{0.4em}{0.9pt}\kern1pt}\catcode`\_=8
+\catcode`\/=13\def/#1{\ifx#1/\char`\/\kern-2pt\char`\/\else\char`\/#1\fi}\catcode`\/=12
+\renewcommand{\url}[1]{{\color{structure}\catcode`~=12\catcode`##=12\catcode`_=13\catcode`/=13\textsf{#1}}}
+
+\usepackage{listings}
+\lstset{basicstyle=\color{structure},
+ language=C,
+ captionpos=b,
+ gobble=4,
+ columns=fullflexible,
+ aboveskip=0pt,
+ belowskip=0pt,
+ moredelim=**[is][\color{structure}]{�}{�},
+ moredelim=**[is][\only<2->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<3->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<4->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<5->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<6->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<7->{\color{structure}}]{�}{�},
+ moredelim=**[is][\only<8->{\color{structure}}]{�}{�}}
+\lstdefinestyle{terminal}{basicstyle=\ttfamily\color{darkgreen},
+ language={},
+ columns=fixed,
+ moredelim=**[is][\color{red}]{�}{�},
+ moredelim=**[is][\color{blendedblue}]{�}{�},
+ moredelim=**[is][\sffamily\it\lstset{columns=fullflexible}]{�}{�}}
+\lstdefinestyle{cmd}{basicstyle=\ttfamily\color{red},
+ language={},
+ gobble=2,
+ columns=fixed,
+ moredelim=**[is][\color{darkgreen}]{�}{�},
+ moredelim=**[is][\color{structure}]{�}{�},
+ moredelim=**[is][\sffamily\it\lstset{columns=fullflexible}]{�}{�}}
+\lstdefinestyle{shy}{basicstyle=\color{lightgray}}
+
+\setcounter{topnumber}{3}
+\renewcommand\topfraction{0.7}
+\setcounter{bottomnumber}{3}
+\renewcommand\bottomfraction{0.7}
+\setcounter{totalnumber}{5}
+\renewcommand\textfraction{0.1}
+\renewcommand\floatpagefraction{0.9}
+
+\setlength{\unitlength}{1cm}
+
+\newcommand{\protectfile}[1]{#1}
+\newcommand{\file}[1]{{\color{structure}\protectfile{#1}}}
+\newcommand{\textarrow}{{\boldmath $\longrightarrow$}}
+\newcommand{\arrowitem}{\item[\textarrow]}
+\newcommand{\newterm}[1]{\emph{\color{darkgreen}#1}}
+\newcommand{\BIGskip}{\vspace{1cm}}
+\newcommand{\shy}{\color{lightgray}}
+\newcommand{\hot}{\color{red}}
+\newcommand{\shyhot}{\color{lightred}}
+
+\newcommand{\sectionnonumber}[1]{\section{#1}\addtocounter{section}{-1}}
+
+\def\showsectionnonumber{{\Large\color{structure}\bf\secname\par}\bigskip}
+
+\def\showsection{\hbox{\Large\color{structure}\bf
+ \vtop{\hbox{\arabic{section}}}\kern1em%
+ \vtop{\secname}\par}\bigskip}
+
+\newcommand{\subsectionnonumber}[1]{\subsection{#1}\addtocounter{subsection}{-1}}
+
+\def\showsubsectionnonumber{{\large\color{structure}\bf\subsecname\par}\bigskip}
+
+\def\showsubsection{\hbox{\large\color{structure}\bf
+ \vtop{\hbox{\arabic{section}.\arabic{subsection}}}\kern1em%
+ \vtop{\subsecname}\par}\bigskip}
+
+\newcommand{\subsubsectionnonumber}[1]{\subsubsection{#1}\addtocounter{subsubsection}{-1}}
+
+\def\showsubsubsectionnonumber{{\normalsize\color{structure}\bf\subsubsecname\par}\bigskip}
+
+\def\showsubsubsection{\hbox{\normalsize\color{structure}\bf
+ \vtop{\hbox{\arabic{section}.\arabic{subsection}.\arabic{subsubsection}}}\kern1em%
+ \vtop{\subsubsecname}\par}\bigskip}