commit 7aefc92849862f4c401d12ba48f84cb3f2fad27e
Author: Jasper Spahl <jasperspahl@web.de>
Date:   Thu Jan 13 11:02:33 2022 +0100

    inital commit

diff --git a/Makefile b/Makefile
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--- /dev/null
+++ b/Makefile
@@ -0,0 +1,12 @@
+program: main.c
+	gcc -g -o program main.c
+
+debug: program
+	gdb program
+
+pdf: README.md
+	pandoc README.md --pdf-engine=xelatex -o README.pdf
+
+latex: README.md
+	pandoc README.md -o README.tex
+
diff --git a/README.md b/README.md
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index 0000000..c325e56
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+++ b/README.md
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+---
+title: Debuging with gdb
+date: \today
+author: Jasper Levin Spahl
+documentclass: scrartcl
+lang: de
+papersize: a4
+
+---
+
+# How to debug with `gdb`
+
+Given we have as simple C program with a bug
+
+```c
+/* main.c */
+#include <stdio.h>
+int main()
+{
+    int balance = 100;
+    int target = 1000;
+    float rate = 0.1;
+    int yeat = 0;
+    do
+    {
+        float interest = balance * rate;
+        balance = balance + interest;
+        year++
+    } while ( balance >= target)
+    printf("%d No. of years to achieve target balance.\n", year);
+	return 0;
+}
+```
+
+To find bug we first have to compile the program with
+`gcc -g -o program main.c`.
+The `-g` flag is used to compile the program with debug symbols.
+Now that we have compiled the program we can open int `gdb`
+
+Because we don't want to type all these long commands everytime we
+compile we can use a `Makefile` to make our lifes easyer.
+
+```Makefile
+# Makefile
+program: main.c
+        gcc -g -o program main.c
+debug: program
+        gdb program
+```
+
+Now writing `make debug` in the terminal will compile the program and
+open it in gdb.
+
+To debug the program we first have to set a breakpoint
+```
+(gdb) b main
+Breakpoint 1 at 0x1141: file main.c, line4.
+```
+
+To run the program in gdb type `run`
+```
+(gdb) run
+Starting program: program
+
+Breakpoint 1, main () at main.c:4
+4               int balance = 100;
+```
+
+To step with `s`
+```
+(gdb) s
+5 int target=1000;
+(gdb) s
+6 float rate = 0.1; 
+(gdb) s
+7 int year = 0; 
+(gdb) s
+10 float interest = balance * rate; 
+(gdb) s
+11 balance = balance + interest; 
+(gdb) s
+12 year++; 
+```
+
+At line `12` we want to take a look at the variables.
+The gdb command for that is `p`
+```
+(gdb) p balance
+$1 = 110
+(gdb) p rate
+$2 = 0.100000001
+(gdb) p interest
+$3 = 10
+```
diff --git a/main.c b/main.c
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+++ b/main.c
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+#include <stdio.h>
+int main()
+{
+	int balance = 100;
+	int target = 1000;
+	float rate = 0.1;
+	int year = 0;
+	do {
+		float interest = balance * rate;
+		balance = balance + interest;
+		year++;
+	} while ( balance < target );
+	printf("%d No. of years to achieve target balance.\n", year);
+	return 0;
+}