I’ve been blogging for quite a long time, under several different names. This blog collects my computer-related posts.
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In my previous curmudgeon post, Writing Without Distractions, I gave version control only a brief mention, and promised a follow-up post. That would be this one. This post is intended for people who are not in the software industry, including not only poets but other writers, students, people who program as a hobby, and programmers who have been in suspended animation for the last decade or three and are just now waking up.
Part 1: Blockchain
Blockchain is the technology behind Bitcoin and other cybercurrencies. That's about all anyone outside the software industry knows about it; that and the fact that lots of people are claiming that it's going to transform everything. (The financial industry, the Web, manufacturing supply chains, identity, the music industry, ... the list goes on.) If you happen to be in the software industry and have a moderately good idea of what blockchain is, how it works, and what it can and can't do, you may want to skip to Part 2.
Interesting couple of articles on Ars Technica:
It's getting so that data breaches aren't news anymore unless they're huge. The Gizmodo article calls it The Mother of All Breaches, exposing 773 million email addresses and 21 million passwords. There's a more complete post by Troy Hunt: The 773 Million Record "Collection #1" Data Breach. Hunt is the person behind the Have I Been Pwned website. That should be your next stop -- it lets you check to see which of your email addresses, usernames, and passwords have appeared in any data breach.
Some day I ought to put together a comprehensive list of privacy-related links. This is not that list; it's just a few of the links that came my way recently, in no particular order.
From king5.com :
Last night around 11pm I was awakened by an alert on my phone telling me that 911 service was down, and giving me an alternat number to call. By morning, it was clear that it wasn't a local problem. A quick search showed that the problem was caused by CenturyLink, which tweeted, blaming it on a
a network element that was impacting customer servicesand saying that they estimated it would be fixed in about four hours.
Most humans multitask rather badly -- studies have shown that when one tries to do two tasks at the same time, both tasks suffer. That's why many states outlaw using a cell phone while driving. Some people are much better than others at switching between tasks, especially similar tasks, and so give the appearance of multitasking. There is still a cost to switching context, though. The effect is much less if one of the tasks requires very little attention, knitting during a conversation, or sipping coffee while programming. (Although I have noticed that if I get deeply involved in a programming project my coffee tends to get cold.) It may surprise you to learn that computers have the same problem.
Recently I started reading this Ruby on Rails Tutorial by Michael Hartl. It's pretty good; very hands-on, and doesn't assume that you know Ruby (that's a programming language; Rails is a web development framework). It does assume that you know enough about software development and web technology to be dangerous. And if you're not dangerous yet,...
It points you at a web site where you can learn enough to be dangerous. Starting from knowing nothing at all.
I have spent the last couple of days backfilling the blog with a selection of relevant posts from my Dreamwidth/Livejournal archive. By the time I was done this afternoon, I had a script that does most of the work of importing, and 20-odd new posts. (Well, old posts. New here.) A little manual editing is still required to correct the occasional tag that’s unique to the original blogging engine. They cover much of my recent writing on security, software, and the web.
There’s an article about a security problem getting a bit of attention lately, Apache Access Vulnerability Could Affect Thousands of Applications. Sounds really scary. Here’s a better article about it, Zero-day in popular jQuery plugin actively exploited for at least three years. Looking at those titles you might think that the problem is either with a jQuery plugin, or Apache’s
.htaccessfiles. It’s neither. The real situation is more complicated. You might think that if you’re not using this plugin on your website, you’d be safe. You’d be wrong. You might think that patching the plugin, or the Apache web server, would solve the problem. You’d be wrong about that, too. The real problem is still there, waiting to bite you in the tail. If you don’t have a website, or don’t allow file uploads, you can stop reading now unless you’re curious. If you do, stick around (or jump to the last section if all you want is the fix).
You may remember from my previous post about Hyperviewer that I’d been plagued by a mysterious bug. The second time the program tried to make a simplex (the N-dimensional version of a triangle (N=2) or tetrahedron (N=3), a whole batch of “ghost edges” appeared and the program (quite understandably) blew up. I didn’t realize it until somewhat later, but there were ghost vertices as well, and that was somewhat more fundamental. Basically,
nVertices, the field that holds the number of vertices in the polytope, was wildly wrong.
If you have a lot of projects in separate
gitrepositories, you're eventually going to want to do some refactoring and put some a subtree or two into their own repository so that you can reuse them. (If everything is under the same repository, you probably moved your tree from Subversion or CVS, and you'll want to split it up. These techniques work for that, too.)
TL;DR: if you bought anything from Newegg between August 14th and September 18th, call your bank and get a new credit card. You can find more details in these articles: NewEgg cracked in breach, hosted card-stealing code within its own checkout | Ars Technica // Hackers stole customer credit cards in Newegg data breach | TechCrunch // Magecart Strikes Again: Newegg in the Crosshairs | Volexity // Another Victim of the Magecart Assault Emerges: Newegg
Singly-linked lists, like the ones found in Lisp, have a lot of advantages. But first, let’s back up a little and start with doubly-linked lists, of the sort that one finds in Java and most other object-oriented languages.
The site is almost presentable at this point; I have started to bring over some blog entries/articles that were originally published elsewhere. Most of these were originally published in my personal blog, so they should be considered cross-posts. Articles that form a series can be grouped using tags.
It’s time to figure out what to do next, in particular about ssavitzky.github.io (ss.g.io for short) and computer-curmudgeon.com (c-c.com). Right now they are simply mirroring one another; it’s time to differentiate them, so that Curmudgeon is about my (incipient) consulting business, and the GitHub site is about software development. Some provision also has to be made for my “resume” site, Stephen.Savitzky.net (S.S.net – the capital letters distinguish it from my “personal” site, steve.savitzky.net). This post is me thinking out loud about what to do about that.
Actually two PSAs.
This started out in a comment, but I think enough people may be struggling with DW's relatively new image upload feature that it's worth making it into a post. And it's a good excuse for posting.
Jekyll works just fine on my laptop. If I continue hosting this site on my own web host, I don’t have to restrict my Jekyll configuration to what GitHub gives me – that opens up the full range of available plugins. It also means that I can drag over some content from other places on the server, if I want to. Like my resume? Yeah, that.
My shared hosting service doesn’t like users to install their own copy of Ruby unless they have their own virtual host – Ruby tends to be a memory hog, especially when it’s running something like Jekyll. Fortunately, there’s an alternative:
gojekyll, a Jekyll clone written in
go. (That’s a programming language – it’s often called “golang” to distinguish it from the Japanese board game.) It’s extremely fast and lightweight. My shared hosting service doesn’t have go installed, but getting it up and running is easy.
Please excuse our dust; we’ll get the construction debris out of the way soon.
Wherein we speak of tags, categories, and content. We also touch briefly on the general inadequacy of GitHub’s implementation of Jekyll, and at greater length on the need for a build system.
Wherein our intrepid blogger reflects on the current state of the site. At this point, things are pretty much the way he wants them.
Wherein our intrepid programmer gets a nice feeling of accomplishment. There is a sidebar, and he explains how to make one of your own. Sort of.
Overriding a theme Wherein our intrepid programmer decides to develop his new Jekyll theme by taking an axe to the best example he could find, which happens to be the default.
Read-Mostly Wherein our intrepid programmer begins to get a bad feeling about this.
… and one step back Wherein our intrepid programmer begins to run into difficulties. This will be an ongoing, um… theme in most of the rest of the series.
Step by step. Wherein our intrepid programmer embarks on the seemingly simple journey from a straightforward but boring and hard-to-maintain website written in raw HTML, to a shiny new website based on Jekyll and hosted on GitHub Pages. We’ll see how simple it really is in the next installment or two.
Today in my continuing series on programming languages I'm going to talk about "scripting languages". "Scripting" is a rather fuzzy category, because unlike the kinds of languages we've discussed before, scripting languages are really distinguished by how they are used, and they're used in two very different ways. It's also confusing because most scripting languages are interpreted, and people tend to use "scripting" when they should be using "interpreted". In my opinion it's more correct to say that a language is being used as a scripting language, rather than to say that it is a scripting language. As we'll see, this is particularly true when the language is being used to customize some application.
In comments on "Done Since 2018-07-15" we started having a discussion of mirroring and cross-posting DW blog entries, and in particular what my plans are for implementing personal blog sites that mirror all or some of a -- this -- Dreamwidth journal.
If you're using the popular social/money-transfer phone app Venmo check your privacy settings!! It seems that the default is that every transaction you make is public! It is difficult for me to express just how broken this is. In case you're having trouble grasping the implications, just go to PUBLIC BY DEFAULT - Venmo Stories of 2017. There you will find profiles of five unsuspecting Venmo users -- one of them is a cannabis retailer -- whose transactions were among the over two hundred thousand exposed to public view during 2017.
Even if you're not a programmer (and most of the people I expect to be reading this aren't) you've probably heard one of your geek friends mentioning "object-oriented" programming. You might even have heard them mention "functional" programming, and wondered how it differs from non-functional programming. The computer curmudgeon can help you.
If you are a programmer, you probably know a lot of this. You may find a few items of historical interest, and it might be useful explaining things to the non-programmers in your life.
Here are a couple of little tricks that may keep you from tearing your hair out in frustration, and in any case will make your posts look better.
If you develop software and haven't just returned from the moon, you've undoubtedly heard that GitHub is being acquired by Microsoft. Depending on your affiliations you might be spelling "being acquired by" as "selling out to". The rest of you are probably wondering what on Earth a GitHub is, and why Microsoft would want one. Let me explain.
If your mail client automatically decrypts mail, read this!
Recently I read a couple of blog posts that set me thinking in some interesting directions. Like most of the things I find on LinkedIn, they were mostly a little annoying, with a few good points. For example, Why You Should Decisively Reject Using Wix gives a lot of good reasons not to use Wix, which is a free website builder and host that lets you throw together a website in half an hour by simply picking a template and dragging and dropping things into it. What's not to like, right? Well,...
TL;DR: Patch your computer NOW! (Or as soon as you can, if you're running Windows or Ubuntu and reading this on Monday -- the official release date for this information was supposed to have been Tuesday January 9th.)
A few days ago I got a comment on my weekly post that went Oohh, you're doing what looks to me like a bullet journal? Only online. So I wrote a quick explanation. And then I realized that I might be doing something unusual, that I ought to write up in more detail. So here you are:
(You may want to start with Part 1)
Xmonad is a tiling window manager. That means that, with very few exceptions, it lays out all of the windows in your workspace so that they completely fill the screen. You can have multiple layouts, and flip between them with a single keystroke. You can bring a workspace (there are 9 by default, but you can add more) to your screen with a single keystroke, or send a window to a workspace.
And the whole thing is configured using a text file that is actually a program, written in the functional language Haskell. I'll get to that later.
As I mentioned about a week ago, I've been trying to write more. And since my current obsession is a program called xmonad, well, ...
This is incomplete: it's about the first day's worth (I've been trying to write about 500 words per day). Comments and suggestions are, of course, welcome.
A "highly critical public service announcement" from Drupal [LWN.net] "Automated attacks began compromising Drupal 7 websites that were not patched or updated to Drupal 7.32 within hours of the announcement of SA-CORE-2014-005 - Drupal core - SQL injection. You should proceed under the assumption that every Drupal 7 website was compromised unless updated or patched before Oct 15th, 11pm UTC, that is 7 hours after the announcement."
Impressive. I think this is an appropriate place to quote one of my father's aphorisms: "A locked car with an open window is NOT a locked car."
If PHP is your open window, you may as well leave the keys on the dashboard where they're easy to see.
- Don Marti www/google-chrome.html
The idea of tabs being first class citizens makes a lot of sense, but why have a sub-window-manager that just manages browser windows in tabs, when you could have a tabbed window manager that can manage everything? I might want a browser and a spreadsheet to share a tab.
One of my coworkers had an equally bad experience with Netscape Calendar: one day it was just gone. Not only had they cancelled the service, but they'd deleted all the user data. They had been careful not to tell their customers of this plan, because they "didn't want anyone to complain."
I'd been contemplating switching some of my domains over to Google for email -- Dreamhost makes it easy to set that up. Maybe not.
Yeah, almost all of my websites are third-party-hosted now. But the hosts are nothing but a mirror for the various internal working directories. And they're going to stay that way. If I can figure out how to do that with some Google's services, I may consider using a few of them.
The title comes from "Gin, Television, and Social Surplus" by Clay Shirky. Somebody asked him "where do people find the time?" to create something like Wikipedia. Wikipedia -- the whole thing, articles and edits and talk pages and translations -- represents some 100 million hours of human thought. TV watching, in the US alone, amounts to some 200 billion hours every year. That's 2,000 Wikipedia projects every year.
Shirky points out that, in the years spanned by the Industrial Revolution, "The transformation from rural to urban life was so sudden, and so wrenching, that the only thing society could do to manage was to drink itself into a stupor for a generation." Gin, and more gin. "And it wasn't until society woke up from that collective bender that we actually started to get the institutional structures that we associate with the industrial revolution today."
The equivalent, in the latter half of the 20th Century, was television. Society is only now waking up from that collective bender. What are you doing with your free time?
I'm not watching TV much these days. Nor movies. Nor listening to radio, even during my commute. Nor even reading books and magazines. I am still drugging myself -- I'm a product of my generation, not yet completely adapted to life in the 21st Century -- but my drug of choice these days is mostly LJ. A decade ago it was Usenet. At least my current drugs are interactive.
Sometimes, my current drugs create things that last. Some of my LJ content finds its way onto my website; my songs and essays are already there. I'm working on it. I came out with a CD over the course of two or three years in, basically, the time I saved by not watching TV. I ought to try not reading LJ so much.
Good post on privacy vs. security, with reference links, posted by
. Via .
In a Jan. 21 "New Yorker" article, Director of National Intelligence Michael McConnell discusses a proposed plan to monitor all -- that's right, *all* -- Internet communications for security purposes, an idea so extreme that the word "Orwellian" feels too mild.
This is really just a matter of formalizing what's been widely suspected for years: that the NSA has been monitoring all the phone and Internet communications it can get to.
"The land of the free and the home of the brave..."
Yeah, right. Try this version.
Excellent post by Don Marti on becoming more productive by going offline. Git (distributed version control, basically syncing on steroids), ikiwiki (offline-rendered wiki), blosxom (offline-rendered blog), and more. It's related to a lot of what I've been saying about keeping control of your own data. In essence, what you want to do is to separate writing from publishing.
- Techdirt: TSA Staffer Hires Buddies To Build Insecure Website For Folks Falsely On Watch List
We've had so many stories of government computer systems or websites that have terrible security or are just useless (but expensive!) that it shouldn't surprise us to hear of another one. Yet, there's always someone who can go a step further. Witness the news that the TSA's website for individuals who find themselves incorrectly on the security watchlist has been found to be insecure, with hundreds of falsely accused travelers exposing personal details by using the site. Even better, it turns out that the company that was hired to build the site got the job in a no-bid contract (meaning there wasn't any competition -- it was just chosen) and the guy responsible for figuring out who to hire just so happened to have been a former employee at that company. So, basically, what happened was that a guy who had taken a job at the TSA hired his former coworkers, with no competition for the job and apparently little oversight, to just build a website that turned out to be insecure. And, of course, without any oversight, it took months before anyone even noticed the site was insecure. And, remember, that this is the TSA we're talking about here -- an organization who's main concern is supposed to be security. I feel safer already.Why am I not surprised by this? The original article is on InformationWeek.
"If you want something to get done, ask a busy person to do it." I haven't been accomplishing much lately, so obviously I'm not busy enough.
There are several seemingly-unrelated projects going on in the household at the moment: I'm starting my next album, the
is starting an HTML class, the servers are getting re-organized, and people have been after the to write a cookbook. Meanwhile I've been thinking about writing my blog locally and mirroring it up to LJ.
They're all more closely related than one might think.
- Freedom to Tinker » Blog Archive » Lessons from Facebook’s Beacon Misstep
Facebook recently beat a humiliating retreat from Beacon, its new system for peer-based advertising, in the face of users’ outrage about the system’s privacy implications. (When you bought or browsed products on certain third-party sites, Beacon would show your Facebook friends what you had done.)
Somebody ping Kanefsky
This blog post was written after an inquiry about Amazon's EC2 and S3 services, but it applies much more generally to anyone trying to run a business and depending on an outside service provider. LJ comes to mind, for example. Amazon's terms and conditions include the following disturbing paragraph, which I suspect is not at all unusual in such places:
We further reserve the right to discontinue Amazon Web Services, any Services, or any portion or feature thereof for any reason and at any time in our sole discretion. Upon any termination or notice of any discontinuance, you must immediately stop your use of the applicable Service(s), and delete all Amazon Properties in your possession or control (including from your Application and your servers). Sections 3, 5, 8 - 12, any definitions that are necessary to give effect to the foregoing provisions, and any payment obligations will survive any termination of this Agreement and will continue to bind you and us in accordance with their terms.
In other words, we can pull the plug on you at any time, on no notice at all, but you still have to pay us if you owe us any money.
Think about your web hosting service, your ISP, your online banking, web email provider, your web storefront provider, your blogging service (gestures toward SixApart),... Which of them have real SLA's (that's Service Level Agreements for us Luddites) and which have terms like Amazon's?
Now: which of them is your business depending on, and what are your disaster plans if they suddenly go belly-up, get taken out by the local flavor of natural disaster, or simply get distracted by the next shiny bubble-of-the-year and decide they don't want to play anymore?
Now, if you'll excuse me, I have to do some serious planning.
- KLone - Embedded Web Server and SDK
KLone is a fully-featured, multiplatform, web application development framework, targeted especially for embedded systems and appliances.
This blog post by Eugene Spafford points out that
- Is not a document interchange format -- it is not designed for document transport
- Is not installed on everyone's machine, nor available for everyone's machine
- Not all versions of Word are compatible with each other
- Results in huge, bloated, files for tiny content (such as memos)
- And of course, Word is commonly a vector of viruses and maicious hacks.
He includes a link to the (plaintext) "bounce message" that he uses to educate people who send him Word documents. Well worth a look.
Similar considerations apply to files produced by PowerPoint, Finale, Photoshop, and other programs. Open-source, cross-platform programs like Audacity and the Gimp aren't immune either: even when they're available cross-platform, you shouldn't use them for email.
If you're actively collaborating with somebody who you know is using the same program and version (I'm upgrading to Audacity 1.3; this isn't just a Microsoft problem by any means), by all means use that program's file format, but put it on a website and email the URL rather than trying to ship the whole darned thing in email. Many email systems will bounce big files anyway.
If you're sending a finished product, use plain text, HTML, or XML if at all possible. Other text-based standards include LaTeX for typeset documents and ABC for music. Images can be sent as PDF or JPEG, formatted documents as PDF, music notation as a zipped MIDI file, and sound files as FLAC or Ogg. But even here they're big enough that you'll want to put them on the web and email a link.
.) ETA Oh, and if you're thinking this was inspired by a particular piece of email, or a particular blog post, it wasn't. Just seemed like a good reminder, especially now that I'm trying to put together a CDROM.
Since I've noticed that a couple of new folks have either joined LJ, or posted after a long absence, and since I just spouted off a comment describing the basic HTML tags, here's another take on it, with the rough edges smoothed off.
Here are the essential tags for LJ. You can get away with nothing but these, and let LJ's automatic formatting take care of everything else.
- AOL publishes database of users' intentions | The Register
Crash-only programs crash safely and recover quickly. There is only one way to stop such software -- by crashing it -- and only one way to bring it up -- by initiating recovery. Crash-only systems are built from crash-only components, and the use of transparent component-level retries hides intra-system component crashes from end users. In this paper we advocate a crash-only design for Internet systems, showing that it can lead to more reliable, predictable code and faster, more effective recovery. We present ideas on how to build such crash-only Internet services, taking successful techniques to their logical extreme.
Sent to me by Aahz, who found the link on a Python mailing list. Intriguing, but really only applies at the lower end of the high-reliability spectrum. For software to get to the point where I'd trust it with my life passing a truck on a two-lane road with oncoming traffic, I'd expect proof-of-correctness on some little single-tasking microcontroller, with all of its state in either registers or ROM.
On the whole I agree with him, especially on the subject of fixed font sizes and frozen layouts. Not that it's going to do any good, of course.
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