↓Skip to main content

Lecture Notes: 01 Intro

··3 mins

Welcome to 2470 #

  • Instructor: Nat Tuck
  • Course: CS2470 Systems Programming in C/C++

Where does this course fit in?

  • You’re a CS major
  • You can write computer programs.
  • In this course, we explore some of the details of how actual programs run on concrete computers.

The plot:

  • To do things, programs need to use hardware resources.
  • 1980 personal computer: one program at a time.
  • Two programs at a time means conflicts (who gets input from keyboard? don’t want to mix output to line printer!)
  • Add a dedicated program to talk the the hardware: the OS. Other programs ask the OS to access shared resources for them.
  • To ask the OS to do stuff for you, you make a system call.
  • This class is about writing programs that use system calls.
  • System calls are different on different operating systems, so we need to pick a specific one to use.
  • We’re using Linux. More specifically, a modern Debian-family Linux.
  • Even with an OS, programs are still written to target a specific hardware archetecture.
  • Compiled programs are binary data - machine code - and different kinds of processors have different machine codes.
  • We’ll be using a common archetecture for desktop / laptop computers, the AMD64 archetecture.
  • A platform is the combination of processor archetecture and OS, for us that’s AMD64 Linux.

Course Resources #

Inkfish #

  • Show Inkfish
  • Show hw01

Syllabus #

  • There’s a schedule. It may resemble what happens.
  • Grades: Homeworks, Labs, Project
  • Homework: These are difficult programming assignments.
  • Labs: These are in-class programming assignments.
  • Project: This is a large, difficult programming assignment.

Cheating

  • Copying code without clear, written attribution is plagarism.

  • If you submit plagarized work, you fail the course.

  • You’re not allowed to share solution code with other students either.

  • If you cheat, you get reported to the college, which is bad.

  • You are given starter code for assignments, you can use that.

  • There is code shown in lecture. It’s not starter code, so using it without attribution is plagarism. This is the one case where I might be lenient on the policy, but I also may just give you an F for the semester on the first offense.

The best way to avoid cheating (and the best way to learn the content in this course), is to personally type your own code. Don’t download other people’s solutions, don’t copy and paste other people’s code, don’t ask some AI tool to generate code, etc.

Introducing C #

// A C program is a collection of functions.
// Here's a minimal program with one function
#include <stdio.h>

int
main(int argc, char* argv[])
{
  printf("Hello C program\n");
  return 0;
}

# Direct C => binary
$ gcc -o hello hello.c
$ ./hello

More stuff to show/say:

  • Command line args
  • A C program is a collection of functions
  • Manpages
  • Built-in types in C: char, short, int, long
  • Types have sizes: sizeof(…)
  • Strings are a trick.

Basic Linux and Vim #

  • Working on the Linux command line.
  • Command line basics: command, arguments
  • Directories, pwd, cd, mkdir, rmdir

vim editor

  • syntax highlighting and auto-indentation
  • editing modes
  • combining
  • navigating with relative moves
  • cutting and copying lines and groups of lines
  • navigating with ? and /