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In the Beginning Was the Command Line (1999)

(web.stanford.edu)
412 points conanxin | 1 comments | 27 Jul 24 06:25 UTC | HN request time: 1.354s | source
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mg ◴[27 Jul 24 07:50 UTC] No.41085093[source]▶
The command line is still king.

Whenever I see new coders struggle, it usually is because they:

    - Don't know the context of what they are executing

    - Don't know about the concept of input and output
On the command line, the context is obvious. You are in the context. The working dir, the environment, everything is the same for you as it is for the thing you execute via ./mything.py.

Input and output are also obvious. Input is what you type, output is what you see. Using pipes to redirect it comes naturally.

Not being natively connected to context, input and output is often at the core of problems I see even senior programmers struggle with.

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1. bloopernova ◴[27 Jul 24 14:15 UTC] No.41086743[source]▶
Yep, I ran a short "introduction to the command line" course for the devs in my team. Afterwards, I noticed that their usage of the vscode terminal was much higher, and folks were more comfortable exploring on their own.

Quick outline of the course, in case anyone wants a starting point:

  * Introduction
    Quick history of Unix

  * When you log in
    Difference between login and interactive shells
    System shell files vs user shell files
    .zshenv for environment variables like PATH, EDITOR, and PAGER
    .zprofile for login shells, we don't use it
    .zshrc for interactive shells
    Your login files are scripts, and can have anything in them

  * Moving Around

  ** Where am I?
    pwd = "print working directory"
    stored in variable $PWD
    Confusingly, also called current working directory, so you may see CWD or cwd mentioned

  ** What is here?
    ls
    ls -al
    ls -alt
    . prefix to filenames makes them hidden
    . is also the current directory!
    .. means the parent directory
    file tells you what something is
    cat displays a file
    code opens it in vscode

  ** Finding my way around
    cd
    cd -
    dirs | sed -e $'s/ /\\\n/g'

  ** Getting Help From The Man
    man 1 zshbuiltins
    manpage sections

  ** PATH
    echo $PATH | sed -e $'s/:/\\\n/g'
    zshenv PATH setting
    which tells you what will be run

  ** Environment Variables
    env | sort
    EDITOR variable

  ** History
    ctrl-r vs up arrow

  ** Permissions
    Making something executable

  ** Prompts
    zsh promptinit
    zsh prompt -l

  ** Pipes and Redirection
    Iterate to show how pipes work
    cat ~/.zshrc | grep PATH
    ls -al > ~/.tmp/ls-output.txt

  ** Commands

  *** BSD vs GNU commands
    BSD are supplied by Apple, and Apple often uses old versions
    GNU are installed via homebrew, and match those commands available in Linux