EECS 201 - Class 1: Getting started

# Overview
1. Announcements
2. Review
3. Q&A
4. Extras
5. Basic assignment
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# Announcements
* Basic - Intro released!
  * Due at the end of Monday, January 26
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# Review
### What is a terminal?
* I/O device/peripheral
* Sends text to a computer
* Receives text from computer to display

### What is a shell?
* Program that the user goes through to interact with the OS
* Graphical and command line varieties
* Command line shells interpret user-entered text and do something with it
  * Navigate through files and directories
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# Review
### File paths
* Describe how to get to a file/directory by traversing directories
* `/` is the directory separator
* "Root" is the highest level/topmost directory
* Absolute paths: start with a `/`
* Relative paths: don't start with a `/`
  * Implicitly start from the current directory
* "Special" directories
  * Each directory contains these
  * `.` leads to the same directory
  * `..` leads to the parent of the directory
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# Review
### Basic commands
* `man`: "manual pages"
* `pwd`: "print working directory"
* `ls`: "list directory"
* `cd`: "change directory"
* `mv`: "move"
* `cp`: "copy"
* `touch`
* `rm`: "remove"
* `cat`: "concatenate"
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# Review
### Command structure
```bash
$ <command> <argument 1> <argument 2> <argument 3>
^     ^    ^     ^
|     |    |     |-- programs are provided these to
|     |    |         interpret (remember argc and argv[]?)
|     |    |
|     |    |-- words separated by whitespace
|     |
|     |-- certain things are actual programs, certain things
|         are handled by the shell ("built-ins")
|
|-- this is called a "prompt" and can take many forms
```
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# Review
### Pipes and redirection
* `|` passes output from one command to the input of another
* `>` sends the output to a specified file instead of a terminal
* `<` reads input from a specified file instead of a terminal
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# Q&A
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# Extras
* Command line text editors
* Terminal pagers
* Shell scripts
* How WSL files work
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# Activity 1
* Count the number of items in a directory
  * `ls` will list out items in a directory
  * `wc -l` will count the number of lines of given _input_
  * `ls` will change its behavior to output items on lines when it's not
    printing to a terminal..
* Now save the output to a file!
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# Activity 2
* Using only your terminal, create a Hello World program in C++ (or your
  preferred language)
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# Basic assignment
* Create an SSH keypair
  * You can use an existing one
* Submit the keypair to the course server
* UMVPN
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# Backups
* Nowadays, with the proliferation of online services, there's no
  excuse to ever lose your important files
* For text-based data, version/revision control is the best solution (e.g. git)
  * More on this in a couple of weeks

* For non-text data, there are numerous options to sync to the cloud
* Free for U-M students
  * 250GB of data on Google
  * 5TB (!) of data on Dropbox
* Paid options
  * Google: $2/month for 100GB, $10/month for 2TB
  * Apple: $1/month for 50GB, $3/month for 200GB, $10/month for 2TB
  * Microsoft: $2/month for 100GB, $10/month for 1TB + Office apps
  * Backblaze: $9/month for unlimited storage, supports client-side encryption
* Use at least one of these options to keep your data safe
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## Environment
* Terminal emulator: __Built-in Mac OS Terminal app__
* Shell: __Zsh__
* Window manager: __MacOS__

### Software
* Editors: __Emacs__, __VSCode__, __Xcode__, __Pico/Nano/Femto__