[C/Learn] Beginners Tutorial

VIM:
  - CMD to start vim [ vim <filename> ]
  - vim has different modes
    * Insert Mode

  - To enter Insert Mode press I
  - To exit Insert Mode press Esc
  - The left of green block is where cursor is
  - To exit do Esc and :q
  - To save do Esc and :w
    * Put :qw to exit and save at same time

C Formatting -
  - #include <headerfile.h>
    * This adds a premade library of functions to use
    * goes at top

  - int main() { return 1; }
    * This is the main function. It has all of the code you want ran first

  - Function(Argument1, Argument2);
    * Dont Forget That Fucking Semicolon

How a C program Works -
  - Algorithm
    * Step by step instructions
    * Computers need very specific instructions

  - Functions
    * Block of code that can be repeated over and over
    * Function definition example

      void example(int number) { // Function definition
          number++;// Adds 1 to number varitable
          printf("%d\r\n", number); // Printf function Call
          return; // Return VOID datatype
      }

    * Calling example function
      - example(5);
      - the 5 is called argument
      - function adds 1 to 5 and prints to screen then exits function

    * Return
      - return is called when you want to exit function
        > can be placed anywhere in function

      - can return any data type (char, int, float, etc)

    * Datatypes
      - A datatype is a type of data like a number or a string
      - There are datatypes located at begining of functions
        > This datatype is for defining the type of data that gets returned

      - Char datatype
        > Also refered to as a string
        > Different Types of char
          * char string1[size]
          * char *string2;
      - Int datatype
        > Integer or whole number

      - Float datatype
        > Any real number aka numbers with decimals

Basic Unix/Linux -
    * Linux is based of unix
    * Terminal/bash are more used in unix/linux than windows
    * C and unix are connected
      - C was originaly designed for unix

    * Directory = folder
    * Basic Commands
      - pwd returns the current working directory (CWD)
      - ls lists everything in your current directory
      - cd <directory> changes CWD to first argument
      - cat <File Path> reads files and prints to screen
      - Flags
        > Flags are arguments passed to programs with -
        > ex1) ls -a
          * lists everything including hidden folders

        > ex2) ls -l
          * lists the long version of ls

      - Directory
        > Absolute Path
          * From the very begining
          * Use / to define as Absolute path
          * Ex) cd /root

        > Relative Path
          * Path relative to cwd (current working directory)
          * Ex) cd ..

        > Root directory
          * The begining of all directory branches
          * /

        > Home directory
          * The directory where your users files are kept
          * First directory when opening terminal
          * ~/

      - Playing With files
        > touch <File Path>
          * Creates a file
          * touch main.c

        > mv <File Path> <To>
          * Moves files
          * mv main.c /tmp/main.c

        > rm <File Path>
          * Removes Files
          * rm main.c

      - Auto Completion
        > You can auto complete commands by typing enough characters and press tab

      - Echo
        > prints text
        > ex) echo "Hello World"
        > Echo to file
          * ex) echo "Hello World" > filename
          * Will overwrite everything in file

        > Echo to file appending
          * ex) echo "Hello World" >> filename
          * Instead of overwriting it appends or adds to file

      - Less
        > ex) less <File Path>
        > Shows 1 page of data from file at a time
        > Useful when theres alot of data in a file

Basics Of C -
    * Format
       - Spacing
         > C is a space insensitive language
         > Used for clarity and ease of reading
       - Also called syntax

    * Variatables
       - Non case sensitive
       - Declaring Varitables
         > Ex) int x;

       - Initializing Varitables
         > Ex) x = 5;
         > stores the integer 5 in varitable x

       - Using Varitables
         > Ex) int y = x / 2;
         > This initializes the varitable y as x divided by 2
       - Expression
         > Anything that will evaluate to a single value