🚀 LAUNCHING A THING TODAY 🚀

My friend @ellane and I are pleased to launch a new mini-course:

🧑‍💻 Ellane learns the command line 🧑‍💻

She mentioned this to me a while ago, so we're going to do it live on Mastodon. Here, in this thread. We're thinking of it like a correspondence course.

You can't fit that much in a post, and formatting here isn't great, so the full posts will be on our mini blog at:

https://commandline.johnnydecimal.com.

We'd love you to follow along.

#LearnCLI

01. Introduction & goals

On Mastodon, @ellane mentioned that she'd like to 'learn the command line'. What she told Johnny was that she wants to:

- understand what the command line IS
- learn how not to stuff up your machine
- learn what language it speaks
- understand what commands DO, where things go
- what's Homebrew, and why use it and what does it do, and how does it do it?

#LearnCLI

https://commandline.johnnydecimal.com/learn/01-introduction-and-goals/

02. What is the command line?

A very high-level introduction to the command line. What even is it? Why would we use it?

You can click a button because some designer in Seattle designed the program to have a button.

But what if you want more granular control? What if there isn't a button for the thing you want to do?

Then you crack open the command line.

Over to you, @ellane.

#LearnCLI

https://commandline.johnnydecimal.com/learn/02-i-want-to-understand-what-the-command-line-is/

@johnnydecimal @ellane I'm really interested to see how this goes! As someone who's lived in the command line for 30 years 😮 I have no idea how I would teach/introduce these concepts to a newbie.

@claudinec @ellane :-) Wish us luck! I can't wait.

@johnnydecimal Thanks, Johnny, this is outrageously exciting to my aspiring-geeky heart!

So I've done my assignment re- layers of abstraction. Makes perfect sense.

Just like my car's ignition button, I'm aware there's an organised, predictable series of events that take place once the button is pushed. Each of those events relies on those that came before it (pistons, oil, petrol, etc), but I don't have to think of any of that when I'm buckling up.

Computers be no different!

@ellane Oh good analogy! That's going to be helpful.

Learning 'the command line' is like learning how to drive. But before we can drive, we need a vehicle.

Let me show you around your new car.

#LearnCLI

https://commandline.johnnydecimal.com/learn/04-let-me-show-you-around-your-new-car/

@johnnydecimal @ellane I know basics. I’ve tried to become a command line pro a few times, most notably through Bart and Allison’s ‘Taming the Terminal’ podcast series. But it has never stuck. I’m going to try again through this series!

@canion @ellane Do it! The more the merrier; you'll catch my errors! :-)

@canion Even if the first few lessons are too basic for you (as I'm the noobiest of beginners), hopefully starting from scratch will fill in any holes in your foundation.

The level of assumed knowledge in every.single.tutorial. I've found up to this point has roadblocked me before I could get started. This one is my first experience with a teacher who is patiently explaining things from the very VERY foundational beginnings. Loving it so far!
@johnnydecimal

@johnnydecimal

This lesson also brought up one of the frustrations I’ve faced in the past when trying to use Terminal.

I’ve pasted in the string I was given (in this case, `printenv`), pressed `Enter,` and a process completed successfully. I then wanted to do something else, but nothing I typed showed up on the screen, even though there was a blinking cursor.

What am I missing? Surely the answer isn’t to close the window and open a new one, is it, but if so, why? (3/3)🧵

@xxxx Hmm, could be! I like this answer.

@ellane
My theory was just that it was a GUI (Graphical User Interface) element. Part of the Terminal app, but not actually part of the command line.

I didn't even think about interrupting a running process 😆
@johnnydecimal

@johnnydecimal
Whoops, didn’t see the reply from @xxxx which basically said the same thing 😅
@ellane

@ellane okay this is a fun thread, I’m here for this…

I don’t know quite what would cause the prompt to not reappear after a command. It’s possible the command was actually still running. There is a way to terminate a running command and thus return to the prompt but I will leave that to your tutor!

@death.au @xxxx @ellane I didn’t see that, can you ping me a link?

@johnnydecimal
micro.blog/xxxx/38517471
I actually had to go to Ellane’s profile on pkm.social (in a browser) to see it. I only looked because she replied.
Ah, the perils of federation…
@xxxx @ellane

@ellane Hmm no, this is not normal.

Here's a little video. I type out `printenv`, hit return, see the result, hit return a few times, do it again. This is what should happen.

You're saying after your first screen of results the window becomes unresponsive?

Try typing vs. pasting, though that shouldn't matter.

https://share.cleanshot.com/kR2SZnj9

@johnnydecimal It was unresponsive yesterday, but worked today. *shrugs*

I found the same thing when trying to use hledger in the past: got in there, but couldn't figure out how to exit.

There's going to be a logical explanation for this behaviour, no doubt, and I'm looking forward to learning more so I don't feel so lost.

#LearnCLI

@ellane Hmm okay let's just keep an eye on that. If it happens again, let me know.

Preparing my response as we speak! Should be there tomorrow.

@ellane I had no idea what `view` did, by the way. Had to type it to see, at which point I realised it was a synonym for `vim`.

You learn something every day…

And you did the right thing hitting the red button aka the ejector seat. 👍

@ellane You have two options to deal with this. You can wrap the file path in quotation marks, which says “treat this as one argument”, or you can precede the space with a \ which says “don’t treat this space like break in the list of arguments, treat it as a literal space within the current argument”. What if your argument needs to include a real backslash? Then use \\ - the first backslash says the next backslash should be treated as a real backslash

But yes, you have stumbled on why heavy CLI users prefer underscores or hyphens to spaces

@ellane note this is similar to markdown, where \* would give you a literal * instead of beginning an italic block

@sam That’s helpful, thanks. I’m familiar with Markdown, but haven’t yet needed to escape those characters. It’s something I’m sure I’ll get used to —no choice, it seems, in the command line environment!

@ellane
My trick is usually to type the first few letters then press the Tab key. It’s a handy shortcut most of the time to fill in long file or folder names, but in my experience it also handles the escaping for you as well.
@johnnydecimal

@johnnydecimal btw love the traffic lights idea!

@johnnydecimal
🙇 Forgive me for skipping ahead, Sensei. Sumimasen.
@ellane

@johnnydecimal If I was typing it I’d have initially thought to put the backslash close to the next word, but now I can see that it’s immediately preceding the word space, which is the thing we need to escape.

I `cd`d to the this/that folder two ways: both `cd this\/\that` and`cd “this/that” `worked. (2/4)🧵

@johnnydecimal Question: is case important? It doesn’t seem to be. I’ve noticed that `cd Desktop` returns `ellane@macbook-pro Desktop % `, while `cd desktop` returns `ellane@macbook-pro desktop %`. It’s the same location each time, so I’ll assume location names aren’t case sensitive unless you tell me otherwise.

One more question: what’s `ttys000`? And why the % sign? I seem to remember a $ sign being there last time.
`Last login: Mon Jun 3 13:29:54 on ttys000`
`ellane@macbook-pro ~ %` (3/4)🧵

@ellane Look at this one more closely!

It should be `this\that` — the same backslash that you use for the escape character.

The puzzle is: how do you include the escape character in an argument _if it’s the escape character?_

@johnnydecimal Classic error! Okay, I've named the folder correctly now. The answer is, you use two of them: `cd this\\that`

@death.au @hyde I should apologise and make it clear that I value feedback on this little endeavour.

If I’m not clear, or if I’m wrong — which will for sure happen — please call it out. Corrections will be made.

And I’m sure @ellane won’t go jumping ahead anyways.

😊

@johnnydecimal No worries at all :)

And @ellane good luck with the CLI :)

Since I learnt it, I cant live without it.

@johnnydecimal Just to check, I opened another window and yep, it said `tys001`.

I played with `ls -la` for different locations on my hard drive, and the `--color=always` one, too. The latter produced mostly one colour, with splashes of another here and there. I suppose we’ll get to the logic behind that later, if it’s important enough to discuss.

When displaying `ls -la` there’s a column on the left with information like `drwxr-xr-x@` that I don’t understand. (2/3)🧵

@ellane @johnnydecimal Hi both, just wanted to say thank you for this open and transparent communication about this learning experience!

I work in IT for some time and its not only a great reminder on how things work but also how many things are logical and others are ambiguous and sometimes confusing. 🙏😌

@ConLuegering I'm delighted you're finding some value in it, all your experience notwithstanding! @johnnydecimal

@ellane I expect your tutor will explain the confusing column soon enough, as it is good to know

…I mistakenly pressed tab to summon auto complete with one quote mark at the beginning of a word—it’s obvious I should have omitted it, but now I’ve got `[dquote>` and I don’t know what to do with it. None of the commands I’ve learned thus far helped (including `logout`, `q`) so I closed the window with the red corner dot and opened a new one.

Is there a way to create a bookmark, a shortcut, to get to a deeply nested folder? Please say yes! (2/9)🧵

`j` and `k` are much more convenient than searching out the up and down arrow keys. `q` for quit? It was really that simple?? Good to know. I’ve been stuck on pages like this in the past, not knowing how to get out.

If spacebar moves down one full page, is there a command to move back up one full page?

I’m seeing character wrapping rather than word wrapping. Is there anything in the Settings to fix this? It disrupts the flow of reading. (3/9)🧵

Righteo, that `h` brings up shortcuts in the file viewer. Is this a file viewer, or a File Viewer? In my mind the former would be built-in, a CLI system-wide way of navigating a file, whereas the latter would be one flavour, like an app.

Is Control-E the same as Control-e? When I see an upper case letter in a CLI context it feels like pressing Shift is implied. So would Control-E actually be Control+Shift+E, or is it case insensitive? Like Command-S on the Mac, for Save. (4/9)🧵

Yes, I touch type. 85 wpm on a good day. (It’s such an important skill in my book that I stooped to bribery, offering each of my children a modest cash prize if they could demonstrate it to my satisfaction. All four did, and now as adults they are proficient where many of their peers are not.)

I pressed `/` to search for this string “F..” in my text file by escaping the two periods. So far so good, but… (5/9)🧵

…what I wanted was to be taken to the first instance, and then to the next when I was ready, etc. Searching like this highlighted the right pattern, but I had to scroll through a very long document to find each instance.

I just typed this: “Why doesn’t autocomplete work with the `less` command? Do I really have to type out the full name of the file I want to view?” before realising I’d been pressing `return` after the first part of the name, rather than `tab`. (6/9)🧵

Until this becomes (new) muscle memory, I can see I’m going to have to slow down and compare what I’ve learned with what my fingers are used to doing.

So. Auto complete worked when searching for a text file to open, but it returned `no such file or directory` until I added the file extension to the name. What’s that all about?

I’m mentally framing this quote: “None of it is difficult; it's just unfamiliar.” (7/9)🧵

A year or so ago I spent a week interacting with my .md notes exclusively in TextEdit (plain text mode), just for the experience. Those raw visuals were a good introduction for becoming familiar with the command line, I now realise!

Wowza, that’s a lot of reading! I scanned through the man page for man itself, and for less. I can see why it’s built in; that’s a lot to remember. Nothing I’m not used to, though. I’m a big keyboard shortcut user in the apps I spend the most time in. (8/9)

@ellane @johnnydecimal jut m'y two cents, when you do :

$ cd a\ dir\ with\ spaces

you can also use double quotes:

$ cd "a dir[tab]

And it will expand it to ;

$ cd "a dir with spaces"

@ellane I have a question, which is slightly off-topic:

It looks like you have been less technical person in the past? If yes: How do you look on IT and apps, now that you took the red pill and left the matrix?

Do you think that "apps should just do their magic" or that this will help you achieve more? Do you believe that programming or IT Stuff is much more different that you thought and now want to unlearn about the truth?

Im just curious on your perception. 😌

@ConLuegering This is a great question. I always thought I was technical, but realise now just how much I’ve been dancing to someone else’s tune. I yet don’t know if I’ll end up writing my own.

This current foray into the command line was sparked by wanting Terminal to do a specific thing I’d heard it could do and realising I was a digital baby all over again, unable to crawl, never mind walk or run.

Re your question on my general attitude to IT, it may be too early to tell.

@ellane Thanks for your reply, I fully agree that it will take some more time to fully identify the impact of this exercise.

Needed to ask it early on, it might sit in the back your head so you can tell me closer to the end. 😉🙏

(I started programming as a hobby again after 12 years and I see for myself how the different the world is or how rusty I have become? 😬😅

@johnnydecimal Yeah, sorry (not sorry) about that! Sorry you have a lot to go through, not sorry I have questions and comments about it all. This is going to be interesting to go back over and read after it’s all neatly and deeply in my brain.

I’m sure I’ll end up rolling my eyes at the simple things I missed, but there’s an important principle here: Someone can be good at one thing and still need to be in nappies (diapers) for a while in another thing. Thanks for your patience!

@ellane Not at all! This is a whole other world here.

In the years running up to 2018 I tried and stalled and tried and failed to start learning some sort of programming language. Started one, stopped. Changed my mind. Started another.

So many times.

The one thing that finally got me was a JavaScript course, sadly now gone*, by a Google engineer. You should have seen how slowly he went.

Pain. Stakingly. Slowly. Like proper baby-steps slowly.

*It was free and now it’s $300/month.

1/2

@ellane And that’s what I needed. That was the ah-ha moment.

Now I can do JavaScript, to an okay standard. Nowhere near many people, but good enough for what I need to do.

I still lean on the web. But because I understand the fundamentals, what I find myself needing is the pointer.

I’m in a dark room and you just need to put my hand on the switch. Then I can do the rest myself.

That’s what we’re going for here.

Fundamentals. Deep understanding.

Slowly. Until the light comes on.

2/2

@ellane *Also*, it’s my job as the teacher to notice and adapt, but that can be hard as we’re just doing this by text.

So if at any point you think we’re going too quickly, please say so.

If there’s a concept that needs to be reinforced, re-explained, whatever: tell me.

@ellane I just realised something! You have access to Learn Excel with Lucy.

Re-watch ‘Functions & Formulas’, and in pt. 2 pay close attention to the TEXTJOIN function.

_Syntactically_ it’s totally different to the CLI.

_Conceptually_ it’s **identical**.

- What’s the command?
- Does it have flags?
- Does it have options?
- Does it take arguments?

This is the thing about computers, and languages: once you internalise the _idea_, the rest is just translation.

4/5

@ellane So the job is to train your brain to think in this really un-human way.

You’re becoming a programmer. The CLI is just a computer to be programmed.

Excel or the CLI. It doesn’t matter.

(For anyone following along, I’ll make that lesson free in the next couple of days and edit this post with a link.)

5/5

@johnnydecimal Will do. I won't know if I've 'got it' until I try to apply the knowledge to something I'm trying to do. I'm looking forward to the real-world applications of this, as I learn best on the job.

@ellane Haven’t forgotten (or got bored of) this! Just had JD work to catch up on, sorry.

@johnnydecimal All good! I'm still working my way through the formulas section of the Excel course. It's probably good to slow things down a bit, so take your time.

@ellane Great. Yeah I was going to write a short summary post to reinforce what’s important to focus on and what’s not. I’ll do it here.

Important:
- The basic <command> <flags/options> <argument> idea.
- This is such a massive leap from clicking a mouse.
- We’ll do a LOT more of this over time.
- Viewing a document; getting around inside there.

Not important:
- Any of the specific flags or arguments to any particular command.
- None of the contents of the man pages! Scary nonsense.

@ellane Let me know when you’d like to move on! No rush.

@johnnydecimal Working on it! I've been on grandma duty, but should be good now to continue.

@johnnydecimal Okay, I've reviewed the Formulas and Functions lesson in the Excel course. I love the foundational nature of it! Even though I already know how to create spreadsheets that reference other cells, it was still enormously helpful to have the structure of the process explained in that kind of detail.

I'm ready to go on!

@ellane Sorry sorry, haven't forgotten! Been a busy week, we've had people through and a bunch of other stuff going on.

@johnnydecimal No need to apologise! I’m very pleased to hear you have a life outside of teaching a random internet stranger how to use the command line.

@ellane You can use whatever you like to edit them. And just dive down to the CLI as required.

But still, I think this is a valuable exercise. So have a play with pico, create a few files, edit a few files, and let me know how you get on.

Next, we’re going to go straight for the hledger installation page. 😬

4/4

#LearnCLI

@johnnydecimal Challenge accepted! You’re right about not needing to use the CLI to edit my files; it’s just a vehicle for learning a skill. A mountain to climb, not to build a house on.

I’m looking forward to the next bit! I messed around with installing hLedger last year, but never understood what I was doing, or how to update to the latest version.

#LearnCLI #PlainTextAccounting

@ellane @johnnydecimal I am genuinely impressed! Welcome to the land of #Vim!

@johnnydecimal @ellane maybe vimtutor can do it too !

Just type in your terminal :

$ vimtutor

@hyde I heard about vimtutor a year ago, and did the first few lessons. Time to crack it open again! @johnnydecimal

@ellane Little CLI hint: `history` shows you stuff you've previously typed.

If you want to repeat one of them, `!xx`, where xx is the number before the command, will do that.

Hitting the up-arrow repeatedly will also call back previous commands. There's a nice way to improve this that I'll tell you about later.

@johnnydecimal Thank you, that's making things easier! I am starting to feel both the simplicity and the power of this, and liking it very much.

@ellane @johnnydecimal Reading back through this and the emphasis on *precision* regarding case in the command line, I wondered what you thought about the "regional" spellings, such as "color" vs. "colour". Do both work? Does it bother you if one is preferred over the other? 🙂

OK, here @ellane asks about Control-E vs Control-E, and @johnnydecimal settles on the side of "not case sensitive."

But in the previous lesson, "Less Is More," in learning how to navigate a text file with search, "To find the next instance of the same search, hit `n`. The previous, `N`."

Isn't that an example of case sensitivity? Or is that a rare exception? Seems akin to "`tab` to move forward, `shift-Tab` to move backward" in many forms... 🤔

@natedunnmi I assumed that code would only recognise the US spelling, color, so that's the one I use.

…Just tried it out, and 'colour' is an unrecognized (not unrecognised) option.
@johnnydecimal

@natedunnmi Definitely looks case sensitive! It seems to be a case of learning which commands need the capital and which don't. Assuming case sensitivity (except for Control-E type of things) seems the safest route.
@johnnydecimal

@ellane @johnnydecimal Was this the "end"? I've tried following the threads here on Mastodon, and I've reached what appears to be the last blog post, "Install some packages"... https://commandline.johnnydecimal.com/learn/19-install-some-packages/

@natedunnmi There’s more to come! Johnny has been busy with a product launch, so we’ll get back to it when he’s got some time to spare. @johnnydecimal

@ellane @natedunnmi Feels like a default that the community has settled on over the years.

Control-[CHARACTER] = not case sensitive, i.e. Ctrl-n doesn't do a different thing to Ctrl-N. Therefore, pick a default, which is to express it as a captial. Maybe that's just clearer?

Whereas 'n' to go forward vs. ‘N' to to back, they're two different commands.

'n' without shift does one thing. 'n' with shift, that is to say ’N’, _does something different_.

Lots of this is just historical decisions…

@ellane @natedunnmi Also note how Mac + Windows is explicit about 'Shift'.

Ctrl+E on a Mac, means ‘control and the E key’.

You want a shift in there, you have to say it. 'Ctrl-Shift-E’.

Oh yeah, and look at your menus! Copy = ⌘C. But you don't have to press Shift to get a capital C.

Paste and match style = ⌥⇧⌘V. Needs a Shift, so the Shift is explicit.