diff --git a/20210607/rtech-20210607.tex b/20210607/rtech-20210607.tex
index 56b7d392521787771c2058bd060480f726683766..af8429b35780ac4ae7c55daa4b02beaf25d32209 100644
--- a/20210607/rtech-20210607.tex
+++ b/20210607/rtech-20210607.tex
@@ -20,7 +20,7 @@
% Attribution-ShareAlike 3.0 Unported License along with this
% document. If not, see <http://creativecommons.org/licenses/>.
-% README: Architekturmerkmale von Prozessoren
+% README: CPU-Stack, Anwender-Software
\documentclass[10pt,t]{beamer}
diff --git a/20210608/hello-1.c b/20210608/hello-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..95066d98a9b3e6713957e0bc8ba4a34569596600
--- /dev/null
+++ b/20210608/hello-1.c
@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+int main (void)
+{
+ char *s = "Hello, world!";
+ printf ("%s\n", s);
+ return 0;
+}
diff --git a/20210608/hello-2.cpp b/20210608/hello-2.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..2ec9589ba98d1a4146aa419c7ba3a1106b0d3f11
--- /dev/null
+++ b/20210608/hello-2.cpp
@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+int main ()
+{
+ char *s = "Hello, world!";
+ printf ("%s\n", s);
+ return 0;
+}
diff --git a/20210608/hello-3.cpp b/20210608/hello-3.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..9c3ba0001dfbfe82610a9260a6418d70d5f7947c
--- /dev/null
+++ b/20210608/hello-3.cpp
@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+int main ()
+{
+ const char *s = "Hello, world!";
+ printf ("%s\n", s);
+ return 0;
+}
diff --git a/20210608/hello-4.cpp b/20210608/hello-4.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..646bbb19440a353ce75eb918a78189b5d1d9f256
--- /dev/null
+++ b/20210608/hello-4.cpp
@@ -0,0 +1,9 @@
+#include <iostream>
+#include <string>
+
+int main ()
+{
+ std::string s = "Hello, world!";
+ std::cout << s << std::endl;
+ return 0;
+}
diff --git a/20210608/logo-hochschule-bochum-cvh-text-v2.pdf b/20210608/logo-hochschule-bochum-cvh-text-v2.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..3725a72c764b4d9ab200553474e4262161f7a5b5
Binary files /dev/null and b/20210608/logo-hochschule-bochum-cvh-text-v2.pdf differ
diff --git a/20210608/logo-hochschule-bochum.pdf b/20210608/logo-hochschule-bochum.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..8cad73dbb48a2b550bf29355b5a6ec895ce091f8
Binary files /dev/null and b/20210608/logo-hochschule-bochum.pdf differ
diff --git a/20210608/main-program-1.c b/20210608/main-program-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..59ea0c0028cbb0885f60b9520010beb9102ae9a6
--- /dev/null
+++ b/20210608/main-program-1.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+void print (char *s)
+{
+ printf ("%s\n", s);
+}
+
+int main (void)
+{
+ print ("Hello, world!");
+ return 0;
+}
diff --git a/20210608/main-program-2.c b/20210608/main-program-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..3fa68b1e00cad4bf51c915d16ef1273375358d76
--- /dev/null
+++ b/20210608/main-program-2.c
@@ -0,0 +1,7 @@
+extern void print (char *s);
+
+int main (void)
+{
+ print ("Hello, world!");
+ return 0;
+}
diff --git a/20210608/module-2.c b/20210608/module-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..1e4e6f7cc61aabe0c26fb797306bab75039f873b
--- /dev/null
+++ b/20210608/module-2.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+void print (char *s)
+{
+ printf ("%s\n", s);
+}
diff --git a/20210608/modules-1.txt b/20210608/modules-1.txt
new file mode 100644
index 0000000000000000000000000000000000000000..ab5cce983cdbbe7f984a7b943e6606337acb5608
--- /dev/null
+++ b/20210608/modules-1.txt
@@ -0,0 +1,22 @@
+cassini/home/peter/bo/2021ss/rtech/20210608> cat main-program-2.c
+extern void print (char *s);
+
+int main (void)
+{
+ print ("Hello, world!");
+ return 0;
+}
+cassini/home/peter/bo/2021ss/rtech/20210608> cat module-2.c
+#include <stdio.h>
+
+void print (char *s)
+{
+ printf ("%s\n", s);
+}
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc -Wall -O main-program-2.c module-2.c -o main-program-2
+cassini/home/peter/bo/2021ss/rtech/20210608> ./main-program-2
+Hello, world!
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc -Wall -O main-program-2.c -o main-program-2 /usr/bin/ld: /tmp/ccUY2lSw.o: in function `main':
+main-program-2.c:(.text+0xc): undefined reference to `print'
+collect2: error: ld returned 1 exit status
+cassini/home/peter/bo/2021ss/rtech/20210608>
diff --git a/20210608/modules-2.txt b/20210608/modules-2.txt
new file mode 100644
index 0000000000000000000000000000000000000000..40b98cc75241797784fbe75e0a4caec52f10a395
--- /dev/null
+++ b/20210608/modules-2.txt
@@ -0,0 +1,24 @@
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc -Wall -O main-program-2.c -o main-program-2
+/usr/bin/ld: /tmp/ccHKsgcU.o: in function `main':
+main-program-2.c:(.text+0xc): undefined reference to `print'
+collect2: error: ld returned 1 exit status
+cassini/home/peter/bo/2021ss/rtech/20210608> ls -l main-program-2*
+-rw-r--r-- 1 peter peter 89 Jun 8 11:24 main-program-2.c
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc -Wall -O main-program-2.c -c
+cassini/home/peter/bo/2021ss/rtech/20210608> ls -l main-program-2*
+-rw-r--r-- 1 peter peter 89 Jun 8 11:24 main-program-2.c
+-rw-r--r-- 1 peter peter 1560 Jun 8 11:27 main-program-2.o
+cassini/home/peter/bo/2021ss/rtech/20210608> file main-program-2.o
+main-program-2.o: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), not stripped
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc main-program-2.o -o main-program-2
+/usr/bin/ld: main-program-2.o: in function `main':
+main-program-2.c:(.text+0xc): undefined reference to `print'
+collect2: error: ld returned 1 exit status
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc -Wall -O module-2.c -c
+cassini/home/peter/bo/2021ss/rtech/20210608> ls -l module-2*
+-rw-r--r-- 1 peter peter 67 Jun 8 11:24 module-2.c
+-rw-r--r-- 1 peter peter 1384 Jun 8 11:29 module-2.o
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc main-program-2.o module-2.o -o main-program-2
+cassini/home/peter/bo/2021ss/rtech/20210608> ./main-program-2
+Hello, world!
+cassini/home/peter/bo/2021ss/rtech/20210608>
diff --git a/20210608/modules-3.txt b/20210608/modules-3.txt
new file mode 100644
index 0000000000000000000000000000000000000000..2d0b64b775277b8354cd3ee81e68da5691c88aed
--- /dev/null
+++ b/20210608/modules-3.txt
@@ -0,0 +1,10 @@
+cassini/home/peter/bo/2021ss/rtech/20210608> nm main-program-2.o
+ U _GLOBAL_OFFSET_TABLE_
+0000000000000000 r .LC0
+0000000000000000 T main
+ U print
+cassini/home/peter/bo/2021ss/rtech/20210608> nm module-2.o
+ U _GLOBAL_OFFSET_TABLE_
+0000000000000000 T print
+ U puts
+cassini/home/peter/bo/2021ss/rtech/20210608>
diff --git a/20210608/modules-4.txt b/20210608/modules-4.txt
new file mode 100644
index 0000000000000000000000000000000000000000..c87ac747ae7471d3ce41d30313017a57602ac378
--- /dev/null
+++ b/20210608/modules-4.txt
@@ -0,0 +1,15 @@
+cassini/home/peter/bo/2021ss/rtech/20210608> nm main-program-2.o
+ U _GLOBAL_OFFSET_TABLE_
+0000000000000000 r .LC0
+0000000000000000 T main
+ U print
+cassini/home/peter/bo/2021ss/rtech/20210608> nm module-2.o
+ U _GLOBAL_OFFSET_TABLE_
+0000000000000000 T print
+ U puts
+cassini/home/peter/bo/2021ss/rtech/20210608> gcc main-program-2.o module-2.o -o main-program-2
+cassini/home/peter/bo/2021ss/rtech/20210608> ldd main-program-2
+ linux-vdso.so.1 (0x00007ffc9d1e1000)
+ libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f73a5a8b000)
+ /lib64/ld-linux-x86-64.so.2 (0x00007f73a5c95000)
+cassini/home/peter/bo/2021ss/rtech/20210608>
diff --git a/20210608/pgslides.sty b/20210608/pgslides.sty
new file mode 100644
index 0000000000000000000000000000000000000000..9a019ce99f03d27a17942facc56fe2145f46b6a6
--- /dev/null
+++ b/20210608/pgslides.sty
@@ -0,0 +1,233 @@
+% 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{amsfonts}
+\usepackage[british,german]{babel} % Yes, really "german" and not "ngerman".
+\usepackage[utf8]{luainputenc} % Without this, umlauts are broken. Weird.
+\usepackage{microtype}
+\usepackage[T1]{fontenc}
+\usepackage{times}
+\usepackage{helvet}
+\renewcommand*\familydefault{\sfdefault}
+\usepackage{graphicx}
+\usepackage{pstricks}
+
+\hypersetup{colorlinks,allcolors=blue}
+
+%% @@@ Not necessary for slides. Why???
+%% Repair kerning: Automatically insert "\kern{-0.15em}" between "//" % (in URLs).
+%\directlua{
+% local glyph = node.id ("glyph")
+% local function my_kerning (head)
+% for t in node.traverse (head) do
+% if t.id == glyph and t.char == 47 then
+% if t.next
+% and t.next.next
+% and t.next.next.id == glyph
+% and t.next.next.char == 47 then
+% local k = node.new ("kern")
+% k.kern = tex.sp ("-0.15em")
+% k.next = t.next
+% k.prev = t
+% t.next.prev = k
+% t.next = k
+% end
+% end
+% end
+% node.kerning (head)
+% end
+% luatexbase.add_to_callback ("kerning", my_kerning, "URL kerning")
+%}
+
+\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}{~$\cdot$~}
+
+\newif\ifminimalistic
+\minimalistictrue
+
+\institute[Hochschule Bochum\sep CVH]{%
+ \makebox(0,0.005)[tl]{\includegraphics[scale=0.72]{logo-hochschule-bochum-cvh-text-v2.pdf}}\hfill
+ \makebox(0,0)[tr]{\includegraphics[scale=0.5]{logo-hochschule-bochum.pdf}}%
+}
+
+\setbeamertemplate{headline}{%
+ \leavevmode
+ \hbox to \textwidth{%
+ \ifminimalistic
+ \strut\hfill
+ \else
+ \rule{0pt}{5.7pt}%
+ \hspace*{8.55pt}\insertinstitute\hspace*{5.7pt}%
+ \raisebox{-30pt}{\rule{0pt}{1pt}}%
+ \fi
+ }%
+ \vskip0pt%
+}
+
+\iffalse
+ \setbeamertemplate{footline}{}
+\else
+ \setbeamertemplate{footline}{%
+ \leavevmode
+ \hbox to \textwidth{%
+ \usebeamercolor{footline}%
+ \usebeamerfont{footline}%
+ \ifminimalistic
+ \strut\hfill
+ \else
+ \,\insertshorttitle\sep
+ \insertshortauthor\sep
+ \insertshortinstitute\sep
+ \insertshortdate\hfill
+ \fi
+ \insertframenumber/\inserttotalframenumber
+ %Folie\,\insertframenumber\sep Seite\,\insertpagenumber\,
+ }%
+ \vskip0pt%
+ }
+\fi
+
+\newcommand{\maketitleframe}{%
+ \ifminimalistic
+ \begin{frame}[t,plain]
+ \insertinstitute
+ \par\vfill
+ \begin{center}
+ {\LARGE\color{structure}\inserttitle\par}\bigskip\bigskip
+ {\large \insertauthor\par}\bigskip\medskip
+ \insertdate
+ \end{center}
+ \end{frame}
+ \else
+ \begin{frame}
+ \vfill
+ \begin{center}
+ {\LARGE\color{structure}\inserttitle\par}\bigskip\bigskip
+ {\large \insertauthor\par}\bigskip\medskip
+ \insertdate
+ \end{center}
+ \vfill
+ \end{frame}
+ \fi
+}
+
+\definecolor{medgreen}{rgb}{0.0,0.5,0.0}
+\definecolor{darkgreen}{rgb}{0.0,0.3,0.0}
+\definecolor{lightred}{rgb}{1.0,0.7,0.7}
+\definecolor{medred}{rgb}{0.5,0.0,0.0}
+\definecolor{bored}{rgb}{0.89,0.0,0.098}
+\definecolor{lightgray}{rgb}{0.85,0.85,0.85}
+\definecolor{orange}{rgb}{1.0,0.5,0.0}
+\definecolor{darkgray}{rgb}{0.4,0.4,0.4}
+
+\newenvironment{experts}{\color{darkgray}}{}
+
+\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}}]{²}{¿},
+ moredelim=**[is][\only<3->{\color{structure}}]{³}{¿},
+ moredelim=**[is][\only<4->{\color{structure}}]{°}{¿},
+ moredelim=**[is][\only<5->{\color{structure}}]{¤}{¿},
+ moredelim=**[is][\only<6->{\color{structure}}]{¢}{¿},
+ moredelim=**[is][\only<7->{\color{structure}}]{æ}{¿},
+ moredelim=**[is][\only<8->{\color{structure}}]{ø}{¿}}
+\lstdefinestyle{terminal}{basicstyle=\ttfamily\color{darkgreen},
+ language={},
+ columns=fixed,
+ moredelim=**[is][\color{red}]{¡}{¿},
+ moredelim=**[is][\color{blendedblue}]{°}{¿},
+ moredelim=**[is][\sffamily\it\lstset{columns=fullflexible}]{²}{¿}}
+\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}]{²}{¿}}
+\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}
+\urlstyle{sf}
+\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{\hbox{\Large\color{structure}\bf
+ \vtop{\secname}\par}\bigskip}
+
+\newcommand{\nosectionnonumber}[1]{\gdef\nosectionnonumbername{#1}}
+
+\def\shownosectionnonumber{\hbox{\Large\color{structure}\bf
+ \vtop{\nosectionnonumbername}\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}
diff --git a/20210608/rtech-20210608.pdf b/20210608/rtech-20210608.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..322cf721cf0e83d6832fadd16f8725b1860f8ac5
Binary files /dev/null and b/20210608/rtech-20210608.pdf differ
diff --git a/20210608/rtech-20210608.tex b/20210608/rtech-20210608.tex
new file mode 100644
index 0000000000000000000000000000000000000000..220bfc8d0444c8872803fdd6c93d12e208706a6a
--- /dev/null
+++ b/20210608/rtech-20210608.tex
@@ -0,0 +1,609 @@
+% rtech-20210608.pdf - Lecture Slides on Computer Technology
+% Copyright (C) 2012, 2013, 2014, 2021 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/>.
+
+% README: CPU-Stack, Anwender-Software
+
+\documentclass[10pt,t]{beamer}
+
+\usepackage{pgslides}
+\usepackage{rotating}
+
+\lstdefinestyle{asm}{basicstyle=\color{structure},
+ language={},
+ gobble=4}
+
+\title{Rechnertechnik}
+\author{Prof.\ Dr.\ rer.\ nat.\ Peter Gerwinski}
+\date{8.\ Juni 2021}
+
+\begin{document}
+
+\maketitleframe
+
+\sectionnonumber{\inserttitle}
+
+\begin{frame}
+
+ \showsectionnonumber
+
+ \begin{itemize}
+ \item[\textbf{1}] \textbf{Einführung}
+ \item[\textbf{2}] \textbf{Vom Schaltkreis zum Computer}
+ \item[\textbf{3}] \textbf{Architekturmerkmale von Prozessoren}
+ \item[\textbf{4}] \textbf{Der CPU-Stack}
+ \begin{itemize}
+ \color{medgreen}
+ \item[4.1] Implementation
+ \item[4.2] Unterprogramme
+ \item[4.3] Register sichern
+ \item[4.4] Stack-Überläufe
+ \color{red}
+ \item[4.5] Puffer-Überläufe
+ \end{itemize}
+ \color{gray}
+% \item[\textbf{5}] \textbf{Hardwarenahe Programmierung}
+ \item[\textbf{5}] \textbf{Anwender-Software}
+ \begin{itemize}
+ \color{medgreen}
+ \item[5.1] Relokation und Linken
+ \item[5.2] Dateiformate
+ \item[5.3] Die Toolchain
+ \item[5.4] Besonderheiten von Mikrocontrollern
+ \end{itemize}
+% \item[\textbf{7}] \textbf{Bus-Systeme}
+% \item[\textbf{8}] \textbf{Pipelining}
+ \item[\textbf{\dots\hspace{-0.75em}}]
+% \item[\textbf{9}] \textbf{Ausblick}
+ \end{itemize}
+
+\end{frame}
+
+\setcounter{section}{4}
+
+\section{Anwender-Software}
+\subsection{Relokation und Linken}
+
+\begin{frame}[fragile]
+
+ \showsection
+ \vspace*{-\smallskipamount}
+ \showsubsection
+
+ Software im Speicher
+
+ \begin{center}
+ \setlength{\unitlength}{0.8cm}
+ \begin{picture}(15,3)(2,-1.25)
+ \footnotesize
+
+ \put(2,1.0){\line(1,0){15}}
+ \multiput(2,1)(0.1,0){151}{\line(0,1){0.1}}
+ \put(2,1.1){\line(1,0){15}}
+ \put(3.5,1.2){$\overbrace{\rule{10\unitlength}{0pt}}$}
+ \only<2->{%
+ \put(3.5,-0.05){\vector(0,1){1}}
+ \put(2.5,-0.05){\line(1,0){1}}
+ \put(2.4,-0.05){\makebox(0,0)[r]{\lstinline|CS|}}}
+
+ \put(4.95,0.7){\line(0,1){0.25}}
+ \put(4.95,0.7){\line(1,0){0.5}}
+ \put(5.45,0.7){\vector(0,1){0.25}}
+ \put(6.65,0.7){\line(0,1){0.25}}
+ \put(6.65,0.7){\line(1,0){0.8}}
+ \put(7.45,0.7){\vector(0,1){0.25}}
+ \put(9.55,0.6){\line(0,1){0.35}}
+ \put(9.55,0.6){\line(-1,0){3.2}}
+ \put(6.35,0.6){\vector(0,1){0.35}}
+ \put(7.25,0.4){\makebox(0,0)[t]{Sprünge innerhalb des Programms}}
+
+ \put(8.50,1.55){\makebox(0,0)[b]{Programm}}
+ \end{picture}
+% \pause
+ \begin{picture}(15,3)(0,-1.25)
+ \footnotesize
+
+ \put(0,1.0){\line(1,0){15}}
+ \multiput(0,1)(0.1,0){151}{\line(0,1){0.1}}
+ \put(0,1.1){\line(1,0){15}}
+ \put(3.5,1.2){$\overbrace{\rule{10\unitlength}{0pt}}$}
+ \only<2->{%
+ \put(3.5,-0.05){\vector(0,1){1}}
+ \put(2.5,-0.05){\line(1,0){1}}
+ \put(2.4,-0.05){\makebox(0,0)[r]{\lstinline|CS|}}}
+
+ \put(4.95,0.7){\line(0,1){0.25}}
+ \put(4.95,0.7){\line(1,0){0.5}}
+ \put(5.45,0.7){\vector(0,1){0.25}}
+ \put(6.65,0.7){\line(0,1){0.25}}
+ \put(6.65,0.7){\line(1,0){0.8}}
+ \put(7.45,0.7){\vector(0,1){0.25}}
+ \put(9.55,0.6){\line(0,1){0.35}}
+ \put(9.55,0.6){\line(-1,0){3.2}}
+ \put(6.35,0.6){\vector(0,1){0.35}}
+ \put(7.25,0.4){\makebox(0,0)[t]{Sprünge innerhalb des Programms}}
+
+ \put(8.50,1.55){\makebox(0,0)[b]{Programm}}
+ \end{picture}
+ \end{center}
+% \pause
+ \vspace*{-0.8cm}
+ Sprünge anpassen: Relokation
+
+ \pause
+ \smallskip
+
+ Hardware-Unterstützung (z.\,B.\ Intel): Speichersegmentierung
+
+ \lstinline{CS} = Code-Segment: Segment-Register oder Selektor
+
+\end{frame}
+
+\begin{frame}[fragile]
+
+ \showsubsection
+ \vspace*{-0.8cm}
+
+ \begin{center}
+ \setlength{\unitlength}{0.8cm}
+ \begin{picture}(15,4.2)(2,-1.25)
+ \footnotesize
+
+ \put(2,1.0){\line(1,0){15}}
+ \multiput(2,1)(0.1,0){151}{\line(0,1){0.1}}
+ \put(2,1.1){\line(1,0){15}}
+ \put(3.5,1.2){$\overbrace{\rule{8.0\unitlength}{0pt}}$}
+ \put(7.50,1.55){\makebox(0,0)[b]{Programm}}
+ \put(12.2,2.2){$\overbrace{\rule{3.0\unitlength}{0pt}}$}
+ \put(13.7,2.55){\makebox(0,0)[b]{Bibliothek}}
+
+ \put(8.45,0.95){\line(0,-1){1}}
+ \put(8.45,-0.05){\line(1,0){5.5}}
+ \put(13.95,-0.05){\vector(0,1){1}}
+ \put(13.95,1.25){\begin{rotate}{45}\normalsize\lstinline{scanf}\end{rotate}}
+ \put(10.15,0.95){\line(0,-1){0.8}}
+ \put(10.15,0.15){\line(1,0){2.5}}
+ \put(12.65,0.15){\vector(0,1){0.8}}
+ \put(12.65,1.25){\begin{rotate}{45}\normalsize\lstinline{printf}\end{rotate}}
+ \put(11.20,-0.25){\makebox(0,0)[t]{Sprünge aus dem Programm heraus}}
+ \end{picture}
+% \pause
+ \begin{picture}(15,4.2)(2,-1.25)
+ \footnotesize
+
+ \put(2,1.0){\line(1,0){15}}
+ \multiput(2,1)(0.1,0){151}{\line(0,1){0.1}}
+ \put(2,1.1){\line(1,0){15}}
+ \put(3.5,1.2){$\overbrace{\rule{8.0\unitlength}{0pt}}$}
+ \put(7.50,1.55){\makebox(0,0)[b]{Programm}}
+ \put(13.2,2.2){$\overbrace{\rule{3.0\unitlength}{0pt}}$}
+ \put(14.7,2.55){\makebox(0,0)[b]{Bibliothek}}
+
+ \put(8.45,0.95){\line(0,-1){1}}
+ \put(8.45,-0.05){\line(1,0){6.5}}
+ \put(14.95,-0.05){\vector(0,1){1}}
+ \put(14.95,1.25){\begin{rotate}{45}\normalsize\lstinline{scanf}\end{rotate}}
+ \put(10.15,0.95){\line(0,-1){0.8}}
+ \put(10.15,0.15){\line(1,0){3.5}}
+ \put(13.65,0.15){\vector(0,1){0.8}}
+ \put(13.65,1.25){\begin{rotate}{45}\normalsize\lstinline{printf}\end{rotate}}
+ \put(12.20,-0.25){\makebox(0,0)[t]{Sprünge aus dem Programm heraus}}
+ \end{picture}
+ \end{center}
+% \pause
+ \vspace*{-0.8cm}
+ Sprünge anpassen: Linken
+
+% \pause
+ \smallskip
+
+ Beim Erzeugen der Datei: statisches Linken\\
+ Beim Laden: dynamisches Linken
+
+\end{frame}
+
+\subsection{Dateiformate}
+
+\begin{frame}
+
+ \visible<1->{\showsubsection}
+
+ Man kann Maschinenprogramme nicht "`einfach so"' in den Speicher laden.
+
+% \pause
+ \bigskip
+
+ Sprünge anpassen
+ \begin{itemize}
+ \item
+ Relokation: Relokationstabelle
+ \item
+ Linken: Symboltabelle
+ \end{itemize}
+
+\end{frame}
+
+\begin{frame}
+
+ \showsubsection
+
+ \vspace*{-0.5cm}
+
+ \begin{center}
+ \setlength{\unitlength}{0.8cm}
+ \begin{picture}(15,6)(0,-1.25)
+ \footnotesize
+
+ \put(0,1.0){\line(1,0){15}}
+ \multiput(0,1)(0.1,0){151}{\line(0,1){0.1}}
+ \put(0,1.1){\line(1,0){15}}
+ \put(0,0.8){\makebox(0,0)[tl]{Ausführbare Binärdatei}}
+ \put(0.5,1.2){$\overbrace{\rule{1.0\unitlength}{0pt}}$}
+ \put(2.0,1.2){$\overbrace{\rule{1.0\unitlength}{0pt}}$}
+ \put(3.5,1.2){$\overbrace{\rule{11.5\unitlength}{0pt}}$}
+
+ \put(0,4.0){\line(1,0){5}}
+ \multiput(0,3.5)(0.5,0){11}{\line(0,1){0.5}}
+ \put(0,3.5){\line(1,0){5}}
+ \put(0,4.2){\makebox(0,0)[bl]{Relokationstabelle}}
+ \put(1.0,3.4){\line(0,-1){1.9}}
+ \put(3.75,3.4){\vector(1,-2){1.2}}
+ \put(4.25,3.4){\vector(1,-1){2.4}}
+ \put(4.75,3.4){\vector(2,-1){4.8}}
+
+ \put(4.95,0.7){\line(0,1){0.25}}
+ \put(4.95,0.7){\line(1,0){0.5}}
+ \put(5.45,0.7){\vector(0,1){0.25}}
+ \put(6.65,0.7){\line(0,1){0.25}}
+ \put(6.65,0.7){\line(1,0){0.8}}
+ \put(7.45,0.7){\vector(0,1){0.25}}
+ \put(9.55,0.6){\line(0,1){0.35}}
+ \put(9.55,0.6){\line(-1,0){3.2}}
+ \put(6.35,0.6){\vector(0,1){0.35}}
+ \put(7.25,0.4){\makebox(0,0)[t]{Sprünge innerhalb des Programms}}
+
+ \put(6,4.0){\line(1,0){5}}
+ \multiput(6,3.5)(0.5,0){11}{\line(0,1){0.5}}
+ \put(6,3.5){\line(1,0){5}}
+ \put(6,4.2){\makebox(0,0)[bl]{Symboltabelle}}
+ \put(6.4,3.4){\line(-2,-1){3.8}}
+ \put(10.25,3.4){\vector(1,-2){1.2}}
+ \put(10.75,3.4){\vector(1,-1){2.4}}
+
+ \put(9.25,1.55){\line(0,1){1}}
+ \put(8.50,2.60){\makebox(0,0)[b]{Maschinenprogramm}}
+
+ \put(11.45,0.95){\vector(0,-1){1}}
+ \put(11.45,-0.10){\makebox(0,0)[t]{\lstinline{scanf}}}
+ \put(13.15,0.95){\vector(0,-1){1}}
+ \put(13.15,-0.10){\makebox(0,0)[t]{\lstinline{printf}}}
+ \put(12.30,-0.50){\makebox(0,0)[t]{Sprünge aus dem Programm heraus}}
+
+ \end{picture}
+ \end{center}
+
+ \vspace*{-1.2cm}
+
+ \begin{onlyenv}<2>
+
+ Ausführbare Binärdatei:
+
+ \smallskip
+
+ Relokationstabelle,\\
+ Symboltabelle für dynamischen Linker
+
+ \smallskip
+
+ Formate: a.out, COFF, ELF, \dots\\
+ Dateiendungen: (keine), .elf, .com, .exe, .scr
+
+ \end{onlyenv}
+
+ \begin{onlyenv}<3>
+
+ Objektdatei:
+
+ \smallskip
+
+ Relokationstabelle,\\
+ Symboltabellen für statischen und dynamischen Linker
+
+ \smallskip
+
+ Formate: a.out, COFF, ELF, \dots\\
+ Dateiendungen: .o, .obj
+
+ \end{onlyenv}
+
+ \begin{onlyenv}<4->
+
+ \strut\\
+ Bibliothek:
+
+ \smallskip
+
+ Zusammenfassung mehrerer Objekt-Dateien
+
+ \smallskip
+
+ Statische Bibliotheken: .a, .lib\\
+ Dynamische Bibliotheken: .so, .dll
+
+ \end{onlyenv}
+
+\end{frame}
+
+\subsection{Die Toolchain}
+
+\begin{frame}[fragile]
+
+ \showsubsection
+
+ \vspace*{-0.8cm}
+ \begin{center}
+ \addtolength{\leftskip}{4cm}
+ \small
+ \newcommand{\vtextarrow}[1]{%
+ \begin{picture}(0,0.8)
+ \put(0,0.8){\vector(0,-1){0.8}}
+ \put(0.125,0.4){\makebox(0,0)[l]{#1}}
+ \end{picture}}
+
+ \framebox{\shortstack{\strut menschliche Gedanken}}
+
+ \vtextarrow{Texteditor}
+
+ \framebox{\shortstack{\strut C-Quelltext}} % (z.\,B.\ hello.c)}}
+
+ \vtextarrow{Compiler}
+
+ \framebox{\shortstack{\strut Assembler-Quelltext}} % (z.\,B.\ hello.s, hello.asm)}}
+
+ \vtextarrow{Assembler}
+
+ \framebox{\shortstack{\strut Objekt- und Bibliothek-Dateien}} % (z.\,B.\ hello.o, hello.obj)}}
+
+ \vtextarrow{Linker}
+
+ \framebox{\shortstack{\strut ausführbare Binärdatei}} % (z.\,B.\ hello, hello.exe)}}
+
+ \vtextarrow{Loader}
+
+ \framebox{\shortstack{\strut Programm im Speicher bereit zur Ausführung}}
+ \end{center}
+
+% \pause
+ \vspace*{-7cm}
+ Automatischer Aufruf:
+ \begin{itemize}
+ \item
+ Entwicklungsumgebungen\\
+ (z.\,B.\ Eclipse, Code::Blocks, \dots)
+ \medskip
+ \item
+ \file{gcc} = Compiler\\
+ \hspace*{3em}+ Assembler\\
+ \hspace*{3em}+ Linker\\
+ \hspace*{3em}+ \dots
+ \medskip
+ \item
+ \file{make} kann \emph{alles} aufrufen
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Besonderheiten von Mikro-Controllern}
+
+\begin{frame}
+
+ \showsubsection
+
+ Kein Betriebssystem\\ % \pause\\
+ \textarrow\ kein Relocator, kein dynamischer Linker\\ % \pause\\
+ \textarrow\ Wir müssen dem Mikro-Controller alles "`mundgerecht"' servieren.
+
+% \pause
+ \smallskip
+
+ \begin{itemize}
+ \item
+ fertiges ROM: Hersteller
+ \item
+ Flash-Speicher und In-System Programmer (ISP)
+ \item
+ Flash-Speicher und Boot-Loader
+ \end{itemize}
+
+ \smallskip
+
+ In jedem Fall: statisch linken, Relokation vorher
+ \begin{picture}(0,0)
+ \color{red}
+ \put(0.1,0.1){\line(1,0){1.2}}
+ \put(1.3,0.1){\vector(0,1){2.2}}
+ \end{picture}\\
+ \textarrow\ ELF-Datei in HEX-Datei umwandeln
+
+ \smallskip
+
+ Format: Intel-Hex-Format\\
+ Dateiendung: .hex
+
+\end{frame}
+
+\setcounter{section}{3}
+\section{Der CPU-Stack\label{CPU-Stack}}
+\subsection{Implementation}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ Speicher, in dem Werte "`gestapelt"' werden: \newterm{Stack}
+
+ \begin{itemize}
+ \item
+ Speicherbereich (ein array) reservieren
+ \item
+ Variable (typischerweise: Prozessorregister) als
+ \newterm{Stack Pointer\/} reservieren \textarrow\ \lstinline{SP}
+ \item
+ Assembler-Befehl \lstinline[style=asm]{push foo}: \quad
+ \lstinline{*SP++ = foo;}
+ \item
+ Assembler-Befehl \lstinline[style=asm]{pop bar}: \quad
+ \lstinline{bar = *--SP;}
+ \end{itemize}
+
+% \pause
+ \medskip
+ Speziell: Unterprogramme
+
+\end{frame}
+
+\subsection{Unterprogramme}
+
+\begin{frame}[fragile]
+
+ \showsection
+ \showsubsection
+
+ \begin{minipage}[t]{4.5cm}
+ Parameter:
+ \begin{itemize}
+ \item
+ Prozessorregister
+ \item
+ CPU-Stack
+ \end{itemize}
+
+ \smallskip
+
+ Rückgabewert:
+ \begin{itemize}
+ \item
+ Prozessorregister
+ \end{itemize}
+ \end{minipage}%
+ \begin{minipage}[t]{5cm}
+ Aufruf:
+ \begin{itemize}
+ \item
+ \lstinline[style=asm]{push IP}\\
+ \lstinline[style=asm]{jmp foo}
+ {\color{red}\boldmath $\longleftarrow$ mov \#foo IP}\\
+ \textarrow\ \lstinline[style=asm]{call foo}
+ \end{itemize}
+ Rücksprung:
+ \begin{itemize}
+ \item
+ \lstinline[style=asm]{pop IP}\\
+ \textarrow\ \lstinline[style=asm]{ret}
+ \end{itemize}
+ \end{minipage}
+
+\end{frame}
+
+\subsection{Register sichern}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ Ein Unterprogramm verändert Registerinhalte.
+ \begin{itemize}
+ \item
+ im Hauptprogramm nötigenfalls vor Aufruf sichern
+ \item
+ im Unterprogramm vor Benutzung sichern
+ \item
+ Kombinationen (manche Register so, manche so)
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Stack-Überläufe}
+
+\begin{frame}[fragile]
+
+ \showsection
+ \showsubsection
+
+ Unendliche Rekursion
+
+ \begin{lstlisting}
+ #include <stdio.h>
+
+ int fak (int n)
+ {
+ if (n <= 1)
+ return 1;
+ else
+ return n * fak (n);
+ }
+
+ int main (void)
+ {
+ printf ("%d! = %d\n", 6, fak (6));
+ return 0;
+ }
+ \end{lstlisting}
+ \begin{picture}(0,0)
+ \put(5,6){\makebox(0,0)[tl]{\begin{minipage}{6cm}
+ Bei jedem Aufruf wird die Rücksprungadresse auf den Stack gelegt
+ und die Variable \lstinline{n} auf dem Stack gesichert.
+ \end{minipage}}}
+ \put(3.7,3.5){\makebox(0,0)[l]{\color{red}$\longleftarrow$ Fehler!}}
+ \end{picture}
+ \vspace*{-1cm}
+
+\end{frame}
+
+\subsection{Puffer-Überläufe}
+
+\begin{frame}[fragile]
+
+ \showsection
+ \showsubsection
+
+ \begin{lstlisting}
+ #include <stdio.h>
+
+ int main (void)
+ {
+ int ID;
+ char buffer[20];
+ printf ("Your ID, please: ");
+ gets (buffer);
+ sscanf (buffer, "%d", &ID);
+ printf ("Your name, please: ");
+ gets (buffer);
+ printf ("Hello, %s!\nYour ID is %d.\n", buffer, ID);
+ return 0;
+ }
+ \end{lstlisting}
+
+\end{frame}
+
+\end{document}
diff --git a/20210608/server-0.c b/20210608/server-0.c
new file mode 100644
index 0000000000000000000000000000000000000000..d9eaf86fe7ad4ac05a647825bcd95d88f62436fd
--- /dev/null
+++ b/20210608/server-0.c
@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+int main (void)
+{
+ int ID;
+ char buffer[20];
+ printf ("Your ID, please: ");
+ gets (buffer);
+ sscanf (buffer, "%d", &ID);
+ printf ("Your name, please: ");
+ gets (buffer);
+ printf ("Hello, %s!\nYour ID is %d.\n", buffer, ID);
+ return 0;
+}