The Command Line Crash Course

[zedshaw]

Well, pleasant surprise people are finding this book. Heads up, it'll be getting a little update soon so that it matches the version that is now an appendix in Learn Python The Hard Way. I stripped out a few commands that weren't as useful and also added some more help on what to do when you get stuck (what I call the "reset"). Check out http://learnpythonthehardway.org/book/appendixa.html for the newer streamlined content.

In general I found these 14 commands end up being the smallest number anyone really needs to do basic CLI work, but keep in mind that the goal of the book is to give someone just enough experience to be able to go through my other books. There are plenty of more in-depth books on managing a server, so I don't bother to duplicate their work.

If you really want to learn how to manage servers and work the CLI, then check out "UNIX and Linux System Administration Handbook (4th Edition)" by Evi Nemeth and friends. My recommendation to people is to get a crappy computer you don't want, put OpenBSD on it following their http://www.openbsd.org/faq/faq4.html guide exactly, use the Nemeth book to configure every service you can and then point a security scanner at your box (like Nessus, or whatever they use today).

Once you can setup an OpenBSD box, get services running on them, and secure those services based on known attacks, then you can pretty much do anything. More importantly, OpenBSD is very bare bones so you learn the core of how a Unix system works and how to configure it, but their docs are very thorough and complete so you can do it if you follow them accurately.

Hope that all helps.

[jaseemabid]

> In general I found these 14 commands end up being the smallest number anyone really needs to do basic CLI work..

What should an advanced user know? Everything provided by coreutils, stuff that goes in /bin etc? Also sed, awk and common tools for simple text processing?

[anth1y]

I can't recommend "UNIX and Linux System Administrator Handbook" enough it has definitely helped my burgeoning career as a sysadmin. Also I've learned tremendously from zed's C, Ruby, and Python. Thanks Zed for putting all of that together. Lastly RIP Evi Nemeth, so many Sysadmins are greatly indebted to your gifts.

[spenuke]

Do you think the same benefit could be had from doing it on EC2, or is installing OpenBSD locally from a CD-ROM essential to your suggestion?

[WestCoastJustin]

Although not as deep as Zed's books/tutoriuals. I have created several screencasts about the topic. Basically, I show you what a UNIX-like filesystem looks like, some common commands, and then show you man pages by example. This should be enough to get someone going and teach them how to learn for themselves.

Crash Course on Common Commands @ http://sysadmincasts.com/episodes/13-crash-course-on-common-...

Crash Course on the Filesystem Hierarchy Standard @ http://sysadmincasts.com/episodes/12-crash-course-on-the-fil...

Crash Course on Man Pages @ http://sysadmincasts.com/episodes/19-crash-course-on-man-pag...

ps. there are many great HN threads about UNIX commands, here are just a few:

https://news.ycombinator.com/item?id=6360320

https://news.ycombinator.com/item?id=6046682

https://news.ycombinator.com/item?id=5022457

https://news.ycombinator.com/item?id=4985393

[stiff]

The "Unix Programming Environment" book by Kernighan and Pike is still the best source for a UNIX command line "course". I love the elegance of this book, I learned most of what is in it already by "osmosis" before buying it, still love to skim it just for how masterly it is written and how nicely the problems are approached, definitely something to aspire to.

[vram22]

Speaking of "The Unix Programming Environment":

I was reminded, by this comment:

https://news.ycombinator.com/item?id=7036920

by danso in this thread (who talked about cp and mv), that I learned, from the K&P book (IIRC), that the commands cp, mv and ln were actually all links to the same executable, which did the right thing based on what name it was invoked by, as found from looking at argv[0]. Checked just now in Linux with:

cd /usr/bin ls -li cp mv ln

on SuSE Linux, but they seem to be different files now ...

The -i option to ls shows the inode number.

[vram22]

+N. I never tire of recommending K&P to wannabe Unixers. I've said to participants of Unix courses I conducted using the book, that it (and K&R - the C book) are like Sanskrit shlokas - both are concise, and sometimes have multiple layers of meaning, which one might not get all of, on a first reading.

[robgering]

Another great resource is "The Linux Command Line: A Complete Introduction." I picked up a lot of command-line fu from this book.

http://www.amazon.com/The-Linux-Command-Line-Introduction/dp...

[superchan]

The Linux Command Line is definitely a good book. It's actually available for free here if anyone is interested: http://linuxcommand.org/tlcl.php

[vram22]

Yes, that one is good. I reviewed it here for O'Reilly:

http://shop.oreilly.com/product/9781593273897.do#PowerReview

Mine is the 2nd review from the top, currently; the one titled "A useful book for beginners to Linux".

[danso]

Understanding the shell, both memorizing its syntax and appreciating how it and the GUI are an abstraction of something deeper (though I find it helpful to think of the GUI as the abstraction for he command line), is under appreciated when it comes to learning to code, so a guide like this is really helpful to point to.

What do people think of the shortness of the chapters? That is, having hem cover one command each? I would lean toward combining similar concepts, such as cp and mv, so that the higher-level capabilities, the ones that make the shell uniquely more powerful than the GUI (such as piping), stand out more...but maybe it's better to have things one at a time?

[justincormack]

The GUI is not an abstraction for the command line, it is a totally unrelated implementation, with literally no layered code. They are both interfaces to the kernel API, but the way they are built is very different.

[bstar77]

I find it interesting that very few people know about the "cd -" command (goto previous directory). I find it invaluable, but never see anyone else use it (this tutorial included).

[minimax]

"cd -" and also using "cd" with no arguments to get back to $HOME are great tips. I also have a bash function called "up" to get back N directories up the hierarchy so I can do "up 5" which is like "cd ../../../../.." but much easier to type.

    up () {
        if [[ $# -eq 1 && "$1" -gt 0 ]] ; then
            local i d
            for (( i = 0; i < $1; i++ )) ; do d="../$d" ; done
            cd $d
        else
            echo "Usage: up N"
        fi
    }

[spenuke]

I didn't know this one, and glad I do now! Is it possible that the other one I wish existed is already commonplace? I'd like to have an arg that cd's to a directory automatically after mkdir'ing it... or mv'ing a file to a directory.

Something like:

mkdir foo -go and mv foo ~/bar -go

... Probably simple enough to script, but I guess I'm too lazy at the moment.

[samstave]

I use it a lot. I wish i could add multiples to go backfurther....

i.e.:

cd /var/log

cd /etc/ssh

cd /home/samstave/Downloads

cd -- (takes me back to /var/log/)

[wyclif]

That's weird. "cd" with options was one of the first commands I learned.

[elipsey]

you just made my day :)

[bauer]

Idea: Create Anki decks to go along with the material. Anki is flashcard software with spaced-repetition learning.

[cdr]

Big fan of https://sivers.org/srs - would have never started using spaced repetition without it.

[e12e]

I don't know -- if you learn this stuff, it is presumably to use it -- so you'll get repetition from actually doing the stuff? This is quite useless knowledge if you're not going to be using the command line IMNHO (I do use the command line all the time -- I don't see why someone should learn to do that if they're not going to use it though...).

[thirdsight]

Please finish the other books as well!

[fennecfoxen]

Command line crash course? I can crash your command-line real easy. :(){ ;|;& };:

[runjake]

Because some people just need to get around in a shell, not obtain an unofficial doctoral on it.

Here, let me quote from the first couple paragraphs of the first page of the book:

  I wrote this book really quickly as a way to bootstrap students for my other 
  books. Many students don't know how to use the basics of the command line 
  interface, and it was getting in the way of their learning.

  This book is designed to be something they can complete in about a day to a 
  week and then get enough skill at the command line to graduate to other books.

  This book isn't a book about master wizardry system administration. It's just 
  a quick introduction to get newbies going.

That said, I always like to see a brief introduction to commands like cut and awk, as they are tremendously helpful for pulling stuff out of text data files and they kind of show off the (simple) power of shell. But I've read the first paragraph of the first page of the book and know that wasn't Zed's goal here.

[xradionut]

You're being pedantic and obtuse. In your world people should get an Automotive Engineering degree before driving.

Zed teaches enough CLI to allow students to accomplish the basics so they can learn Python or C. Ideally they will expand on the material and also complete the bonus assignments in the material.

And man pages suck for absolute beginners. There's too much information overload and a beginner hasn't the context to know what is useful for his immediate needs.

[kmfrk]

Is it me, or does the HTML version not have any "Next/Prev" pagination buttons?

[jere]

Yup. I'm reading Learn Python The Hard Way and it's the same.

I'm actually glad it's set up that way. I assume the paid version is more streamlined. I can't get too upset that I have to hit an extra button to access free content.

[Dewie]

The problem I had when I wanted to read a somewhat in-depth tutorial on Linux / the Linux terminal (one or both), is that the tutorial said that it assumed that you were a sysadmin. What? I couldn't just be a regular user who has none of the experience and few of the needs of a sysadmin? No wonder Linux has a reputation for being needlessly impenetrable.

(I don't recall the exact tutorial or if it is representable of such tutorials in general.)

[dded]

I heartily second Stiff's recommendation for Kernighan and Pike. (And being from the 80s, it assumes more of a multi-user Unix environment as apposed to a sysadmin p.o.v.)