0x00. C - Hello, World

Resources

Read or watch:

• Everything you need to know to start with C.pdf (You do not have to learn everything in there yet, but make sure you read it entirely first)
• Dennis Ritchie
• [“C” Programming Language: Brian Kernighan](https://intranet.alxswe.com/rltoken/W4oygfMgAp5Hyc7o6QuSYQ ""C" Programming Language: Brian Kernighan")
• Why C Programming Is Awesome
• Learning to program in C part 1
• Learning to program in C part 2
• Understanding C program Compilation Process
• Betty Coding Style
• Hash-bang under the hood (Look at only after you finish consuming the other resources)
• Linus Torvalds on C vs. C++ (Look at only after you finish consuming the other resources)

man or help:

• gcc
• printf (3)
• puts
• putchar

Learning Objectives

At the end of this project, you are expected to be able to explain to anyone, without the help of Google:

General

• Why C programming is awesome
• Who invented C
• Who are Dennis Ritchie, Brian Kernighan and Linus Torvalds
• What happens when you type gcc main.c
• What is an entry point
• What is main
• How to print text using printf, puts and putchar
• How to get the size of a specific type using the unary operator sizeof
• How to compile using gcc
• What is the default program name when compiling with gcc
• What is the official C coding style and how to check your code with betty-style
• How to find the right header to include in your source code when using a standard library function
• How does the main function influence the return value of the program

Copyright - Plagiarism

• You are tasked to come up with solutions for the tasks below yourself to meet with the above learning objectives.
• You will not be able to meet the objectives of this or any following project by copying and pasting someone else’s work.
• You are not allowed to publish any content of this project.
• Any form of plagiarism is strictly forbidden and will result in removal from the program.

Requirements

C

• Allowed editors: vi, vim, emacs
• All your files will be compiled on Ubuntu 20.04 LTS using gcc, using the options -Wall -Werror -Wextra -pedantic -std=gnu89
• All your files should end with a new line
• A README.md file at the root of the repo, containing a description of the repository
• A README.md file, at the root of the folder of this project, containing a description of the project
• There should be no errors and no warnings during compilation
• You are not allowed to use system
• Your code should use the Betty style. It will be checked using betty-style.pl and betty-doc.pl

Shell Scripts

• Allowed editors: vi, vim, emacs
• All your scripts will be tested on Ubuntu 20.04 LTS
• All your scripts should be exactly two lines long ($ wc -l file should print 2)
• All your files should end with a new line
• The first line of all your files should be exactly #!/bin/bash

More Info

Betty linter

To run the Betty linter just with command betty <filename>:

• Go to the Betty repository
• Clone the repo to your local machine
• cd into the Betty directory
• Install the linter with sudo ./install.sh
• emacs or vi a new file called betty, and copy the script below:

#!/bin/bash
# Simply a wrapper script to keep you from having to use betty-style
# and betty-doc separately on every item.
# Originally by Tim Britton (@wintermanc3r), multiargument added by
# Larry Madeo (@hillmonkey)

BIN_PATH="/usr/local/bin"
BETTY_STYLE="betty-style"
BETTY_DOC="betty-doc"

if [ "$#" = "0" ]; then
    echo "No arguments passed."
    exit 1
fi

for argument in "$@" ; do
    echo -e "\n========== $argument =========="
    ${BIN_PATH}/${BETTY_STYLE} "$argument"
    ${BIN_PATH}/${BETTY_DOC} "$argument"
done

• Once saved, exit file and change permissions to apply to all users with chmod a+x betty
• Move the betty file into /bin/ directory or somewhere else in your $PATH with sudo mv betty /bin/

You can now type betty <filename> to run the Betty linter!