Q&A: Shell Trickery

Here’s a few questions from people regarding the shell that are just simple misconceptions about what it does or questions about small little concepts.

Finder Tracking Bash

My question is in regards to the Appendix Exercises. So I am operating on a MacBook Air, and for my Terminal, I am typing out my commands. I also have open my directories folder so when I am doing commands, I can see the effect of it. What confuses me is the cd ~ command. Let’s say I click on my documents and it takes me to a subfolder. I then go back to the Terminal application and when I type in cd ~ it doesn’t take me back to the home page. Does the cd ~ only operate theoretically?

The ~ is an alias for “wherever my home directory is”. Your terminal does this because your home could be in different places on different Operating Systems (OS). Try this:

cd ~

On a macOS computer, you’ll probably see something like:


Now if you’re on a Linux computer it’d be:


And on PowerShell it’d be even more different depending on the Windows version you use.

Also, I think maybe you expect that cd ~ in your Terminal would also change your Finder window? There isn’t that much of a connection between the two (although that’d be kind of awesome). It’s more that, when you make changes in a directory, they’ll show up in Finder. Doing a cd to a directory doesn’t change it though, so you don’t see that happen in finder as well.


I just wanted to tell you how much I appreciate your teaching method. It suits me perfectly.

I had purchased 2 books before yours and tried several online videos and websites Yours was the first time and place I felt I was actually leaning things from the ‘ground up’, Especially helpful was your Powershell crash course. Just beautiful.

I’m on Exercise 11 and just about to watch your video. But I wanted to tell you about trying escape sequence \a. At least on my computer, it makes a cascading chime sound when I insert it into a string and execute in Powershell. You probably already knew that. You’re so smart.

Thanks again for all the thinking you’ve obviously done on how to best teach programming.

Ahhhh, that’s called the “bell”. I guess in PowerShell it’s way more awesome than on Unix because with Unix it’s just an irritating “BEEP”.  I sometimes use that to tell me when a long running script has finished on a remote server.  I just have the script print out a large number of \a beeps at the end, and then when I hear the classic unix BEEP I know it’s done.

But, on my macOS machine I had to re-enable it to make the bell work.  I probably disabled it because the beep is annoying and the bash shell we all use loves to beep at you for everything.  Completing a file? BONK BONK BONK! Backspace one character too far?  BONK BONK BONK. To turn it on (or off, if you hate that like I do), you go to Preferences in Terminal, go to Advanced panel, and click “Audible bell” like I have here:

Anyway, you’re welcome. I’m glad you’re getting along with it well and enjoying it.  Now I’m going to go and turn off this bell so I don’t go insane.

\v \f Weirdness

This question comes from the Gitter chat so I cleaned it up into a paragraph format:

Hi all, anybody having different outputs when using escape sequences from exercise 10?
Trying to use linefeed “\f”.
I’m using ASC11 linefeed (LF) and I’m getting a female symbol instead of a return indentation.
Here’s the code I’m running:
asc11_formfeed = “Using ASC11 formfeed (FF) \f escape”
And the output is:
Using ASC11 formfeed (FF) ♀ escape
I’m using Windows 8.1, Powershell, IDEs Visual Studio Code and Atom.
I’m also having the same issue using ASC11 vertical tab (VT), and the output gives me a male symbol.
I haven’t tried it on Mac or Linux yet.

Apparently, on Windows if you use \f you get the symbol for “female”, and if you use \v you get the symbol for “male”.  I have no idea who thought that up over at Microsoft, but it’s weird that \v doesn’t produce the symbol for Venus (the “female”) symbol.  These are also super old computing characters so I have no idea why they decided to just change them after 60 years.  I’m sure someone in the comments will have a reason why.

Anyway, different terminals will have different support for these escape sequences.  These escape sequences are very old, and come from when computing was done on huge printers connected to huge computers like this one:

IBM 1403 Line Printer, Photo by waelder CC BY 2.5
By waelder – Own work, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=1962607

Those codes were intended to move the printer head and feed mechanism around so you could do very fancy things like draw boxes around columns for you boss to get that big promotion.  These printers were a lot like a gigantic typewriter in the beginning, and then evolved to dot matrix, then laser printers, then inkjet, and now we just avoid printers completely unless we have to fax something to an ancient government office that still has one of these things in the basement doing important work.

At one point people figured out that different letters and positions on these printers created different musical tones, and would spend all night figuring out how to print Jingle Bells and other 1950s pop tunes on their printer.  That was the 1950s version of Skyrim.  I think today if our printers started making music we’d assumed the printer was hacked and throw it in the garbage.

Since nobody really interfaces with a computer through a printer these codes have become mostly obsolete except for \n, \t, and \r in some cases.  The \n is a “new line”, and on Unix that’s all you need to move the “print head” (cursor) down one line, and back to the beginning line position.  The \t does a tab, which moves the print head (cursor) to the right a certain number of spaces, usually 8 (but if someone uses Emacs then it’s random).  Finally, the \r is mostly used on Windows because they decided that \n should only go down to the next line, and \r should “carriage return” to the first position.  Basically, Microsoft was being pedantic about “carriage return, line feed” so they made everyone actually explicitly write a \n\r to get the new line.  It was one of the very earliest examples of “Well, actually, ” on record (unless you count Leibniz’s writings to Newton).

You’ll find out quite a bit of how computers work now comes from how mainframes worked in the early days of computing.  This is why Python’s (every language’s?) files seem so strange to work with, why these escape codes are so weird, and why vi is so awesome.  I’ll cover more of this in a later blog post on the history of computing that we still deal with today.

Learn Python 3 The Hard Way is now fully released and ready to download.  12 hours of video covering 52 exercises in Python 3 for beginners.  You can buy it at http://bit.ly/buylp3thw and read a free sample at http://bit.ly/lpy3thw to see if you’ll like it before you buy it.

Learn Elixir The Beast Mode Way

I’ve been meaning to start learning a new language for a series of books after Python.  My list is pretty long, including Nim, Elixir, Go, Rust, JavaScript, and I even might, just maybe, who knows, do a PHP7 book.  Currently though I have to do three more courses covering Python before I can move on to the next book, but I do want to start getting off Python for my business software soon.

The first thing I’d like to replace is my current Django web stack.  It works, and powers my things, but honestly it’s not the greatest functionality.  I’d love to just code a replacement in anything else, but my time is limited.  I have to work on books right?  Gotta record those videos.

A while back I heard that there’s people who hate my books for total beginners because they are too repetitive and slow.  Alright, sure, if it’s going too slow then chances are it’s not the right book for you.  I actually admit that the book is not for people who can’t handle doing some rote work or are already experts.  No book can perfectly train everyone, and it’s insane to expect my book aimed at a person with zero knowledge to also train everyone else.

But, I’m a problem solver, and I like to solve my problems by combining many things at once.  Solving one problem is boring.  I need to do three at once:

  •  I have a problem that I’d like to learn a new language to do some web development and replace my current Django stack.
  • I also have the problem that I need to learn a new language for my next book.
  • I then have this problem that people who feel my beginner books are beneath them seem to think the books don’t work for anyone else.

I believe there is a class of person who feels they can’t learn by practice, but only that they can learn by “building stuff”.  I don’t really write books for them, but there was a tickle in the back of my brain that said, “You sure?”

Then it hits me!  I got my next book Learn More Python 3 The Hard Way in the works, I need to learn Elixir, well why don’t I just try to do the Learn More exercises in Elixir as my way to learn Elixir?  Then when I’m done I’ll have learned enough Elixir to work on my own site, and then I can probably do a Learn Elixir The Hard Way, and then…

Wait! What if I do a “Learn Elixir The Beast Mode Way”, or probably a better title because that’s super weird, but I think you know what I mean.  What if I take the projects in Learn More Python The Hard Way, do them in Elixir, then add a large initial “crash course” that teaches enough Elixir to make you dangerous enough to do the projects?  Then, the only structure is the projects, and you can do those in almost any order you want.

I’m actually very into this idea now.  I freely admit that when you’re an expert that rote practice style of learning isn’t very useful.  Learn More Python is kind of the list of projects I work through when I’m learning a new language, so why not just do them with Elixir too?

Starting maybe tomorrow or next week (time permitting) I’m going to “beast mode” Elixir using the projects from my Learn More Python The Hard Way and probably find a place to post the results.  I think what I’ll do is go through this awesome Elixir School website as the fast crash course part, then I’ll start going through my book using Elixir.  If it works then this may become the new format for future books aimed at people who aren’t total beginners.

Learn Python 3 The Hard Way Officially Released

The Good News

I’m happy to announce that Learn Python 3 The Hard Way is officially released and will be hitting Amazon, Barnes & Noble, and InformIT (Pearson) tomorrow.  I spent quite a lot of time revising this book to fit with Python 3 and also making it dovetail nicely into my next book Learn More Python The Hard Way.  The Python 3 edition of my book now includes 12 hours of video instruction.  All redone in 1080p HD video with me doing more than just typing the code in.  I’m now going through the code and showing you how to run it, break it, pitfalls, debugging, and applying different techniques as I go.  I even have videos that show you how to setup your own Linux Virtual Machine if you want to learn Linux.

I also put in a lot of effort to make this version of the book work well with Windows, Linux, and macOS.  I bought a Microsoft Surface book and did all of the videos right in Windows, so I know the book works well with Windows.  I then have special install videos for macOS and Linux in the key places where macOS differs from Windows.  To make the book work seamlessly with all three platforms I changed up the installation instructions so that you use the same editor on every platform.  That way, even though you’re watching me on Windows, it looks and works almost exactly the same as on macOS and Linux.  Just Python, Terminal, and a text editor that works on all three (Atom or Visual Studio Code).

Where To Buy It

You should also be able to buy it at local book stores, especially Barnes & Noble, but it might be a few days before they hit the shelves.

Nostalgia Time

Since I released the book in 2010 I have given it freely to about 12.5 million people. If you look at the Populations of US States I’ve helped enough people to fill about 13 of the lower populated US states.  The number of people I’ve helped for free is greater than each population of all but 6 US states.  This book as been a labor of love almost entirely from me with help from key people along the way, but otherwise a one man show.  I only recently began to realize how remarkable this is that a single person could have so much impact on the lives of so many people.  I am really honored that I could help everyone, and if you know me I’m not the type of person to toss around words like that easily.  When I say I am humbled by how many people I’ve reached and the number of lives I’ve changed, I really truly mean it.

When I started this project I just wanted to help people learn to code before technology destroyed them.  All I saw in 2010 was the rise of predatory technologists taking advantage of people who couldn’t defend themselves because they didn’t know the basics of computing.  Before my books there was this general belief in computing that only “special” people could learn to code, and that it was pointless to teach anyone who didn’t start when they were 12.  I knew that wasn’t true because I really didn’t learn to code until I was 19 years old and could by my own computer after joining the US Army.  If I could be a competent successful programmer after having started over at 19 years old, then anyone could.  Before I wrote Learn Python The Hard Way programming education books either patronizingly assumed you were a child, or assumed you’d already been programming for years.  My book assumed nothing about the reader other than they had a computer and could copy code, and it worked.  Now people all over the world are attending bootcamps, learning to code, and it’s (hopefully) no longer assumed that you have to start coding at 12 to make a computer do things.

I really believe that my books proved that you don’t have to be special to learn to code, you just have to put in the effort to learn it.  But, I also hope that my books also relay just how much I love programming.  I may hate the software industry, but making a computer do things has been one of the greatest saviors of my life.  It dragged me out of extreme poverty, taught me math and how to write, gave me a job, and help me feel less useless in the world.  I really want my books to be a reflection of what I wish I had when I was younger, trying to learn to code late at night on a Tandy computer for those brief years when I caught a glimpse of what was possible.  Those late night hacking and talking to friends on my local BBS.  The text adventure games and those first bugs I fixed which made me feel like a GOD (followed by the 1000 other bugs that taught I am definitely not a god).

Now For Some Bad News

Looking back on the last 7 years I realized that I’ve helped a tremendous number of people, but I recently started to think that I could help people even more if I sold my books.   Right now, I’m a one man show apart from a little bit of help from my publisher.  I do everything from video, to writing, to even system administration for my own servers.  I struggle to keep costs as low as possible so I can keep working, but if I charged for my books I could do so much more:

  • I could open a low cost or even free online school for junior developers.  One that didn’t skim off the top of your salary and make you quit your job for maybe getting hired at a terrible startup.
  • I could produce even more courses for emerging languages that the big publishers ignore.  I could create full courses for Nim, Rust, Elixir, and anything else that needs training materials.
  • I could hire people to help with the production and produce the books faster.
  • I could also branch out into arts education, producing free courses on painting and drawing and do for art what I did for programming.  I could prove that you don’t have to be special to make art in the same way that I proved you don’t have to be special to code.

I thought about this for a long time, but I struggled with the moral dilemma of wanting to help people who need free education, while needing money to make more free education.  Being as it’s just me–and there’s no way I’m getting a loan or VC money for making free stuff–I realized I’d need to start charging for my big books in order to fund other projects.  I talked with friends and they all said I should just shut up and charge, I’ve done enough helping.  But, it never felt right to me, so I kept my books free to read and tried to devise other ways to pay for my new projects.  I wanted to teach people how to paint for free, but I need help and need to pay people for that help.  I needed help with editing, running the operations, and video production, but I couldn’t pay anyone a fair wage for their work.  I was stuck.

Then I recently found out that members of the Python Software Foundation (PSF) have been actively trying to have my book removed from other books and websites.  I received several chats logs from trusted associates that show PSF members contacting authors and demanding that they stop referencing my books.  Believe it or not, it’s because I said Python 3’s strings suck or that Python 3 sucks.  I’m not kidding.  They are so petty that they are actively trying to destroy the one book that is potentially helping the most people become Python programmers simply because…I don’t like how they implemented Python 3.  I realized that I’m now sending beginners into a community that actively ostracizes and punishes anyone who dissents against the decisions of the PSF members.  I simply can’t support the PSF anymore given these actions, and I can’t send them new people if this is how they treat anyone disagreeing with them.

At that point the decision became much clearer.  If I charge for my Python books I can help even more people and also give people real jobs working for me.  Charging for my books also satisfies the PSF’s demands that my book be taken down, and it will stop directing beginners toward their organization.  It makes me sad that I won’t be able to continue helping so many, but I’m hoping that with people buying my Python books I can create more courses for people to consume at very low cost or even free.

The Future

Starting July 8th, 2017 both my Python 2 and Python 3 books will be no longer free to read.  I will keep Learn Ruby The Hard Way free for anyone who wants to learn to code and can’t afford my other books.  Ruby is a fine language to learn to code, so this should continue my mission to help people who can’t afford programming education.  I will also make books free to read while I’m developing them so people can benefit from them before I officially release them.  This seems like a fair trade since you get early versions of my books for free and I get feedback on them while I produce them.

I understand that this will probably put a large number of people out on a limb, but I hope everyone will understand that doing this will help me help more people in the future.  I also hope that you understand that I cannot continue helping the Python Software Foundation given their track record of abuse.  I’m deeply sorry if this impacts your life in any way, but if you need help feel free to email me at help@learncodethehardway.org and tell me what you need.

Thank you for understanding.