Take back your privacy
Recent surveys have found that 76% of [the most visited] websites in the world cotain trackers from google and 24% contain trackers from facebook. This has been reported by CNBC, PC World, The Verge, Fortune, and Breitbart.

Almost anywhere you go on the internet, they are following you, building a profile on you, and selling that information, your information, to the highest bidder. Even if you don't have a user account for google or facebook "services," they've built a profile of you using this surreptitiously collected data.

It turns out there are some steps one can take to prevent these companies from following you wherever you go. It's not perfect, but it helps a lot. First, don't use Chrome. Second, install ad-blocker plugins for your browser. Third, use your firewall.

It turns out Google and Facebook are large enough that they have their own Autonomous Systems (AS) composed of numerous subnets. Google owns AS 15169, while Facebook owns AS 32934. Using a little bit of shell, it's relatively easy to look up all the subnets owned by these companies.

whois -h whois.radb.net -- '-i origin AS32934' | grep "^route:" | awk '{print $2;}'
whois -h whois.radb.net -- '-i origin AS15169' | grep "^route:" | awk '{print $2;}'

That's a lot of subnets. Because I have different operating systems on different computers and still want to block traffic to and from all those IP addresses, I've written some simple scripts to add rules to various firewalls. I have scripts for IPFW on FreeBSD, IPTables on Linux, and the Windows Firewall that should work from XP SP3 through Windows 10. I've only tested it on Windows 7 and Windows 10, and it worked in those.

All of these scripts can be found in this directory. The IPFW and IPTables scripts are self-contained. For the Windows command shell batch files, the *ips.txt files are also needed.

I have to say, the internet looks very different with these firewall rules in place. There are noticeably fewer advertisements and pages load faster. Embedded YouTube videos and Instagram photos don't appear. Sometimes the frame disappears, sometimes you get a "failed to connect" page appearing in a frame in the middle of a page. (Yes, these rules block YouTube and Instagram; they are owned by google and facebook and reside in the subnets owned by those companies.) On a relatively rare occasion, I come across a site using some sort of javascript or css or something hosted by a machine in one of those ASs and that will be blocked. Sometimes the site handles that gracefully, sometimes it stops being functional. A small price to take back your life.

Update: Twitter has trackers on a decent amount of sites out there too, so I've added scripts to block Twitter's AS 13414 as well. Those scripts are in the same directories as the others.

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1454815466
Beautiful https://www.instagram.com/p/BBeDsOSrXEk/

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Optical Illusion
I saw this today. I thought it was interesting.

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WTF?
I'm used to guitarists mocking the bass and bassists. It doesn't bother me too much. But this... This irritated me. A lot.
Today at work there was a group of people talking about Rock Band and Guitar Hero 3. None of them actually know how to play intstruments but they claim to be great at these games. They seem to believe this entitles them mock bassists.

• "Oh man, bass is so easy. It's the guitar that's the hard part. Yeah, I'm on expert on the guitar."
• "Yeah, bass is so stupid."
• "So It's me, my brother, and my sister. I play guitar, he's on drums, and my sister sings."
  "what about bass?"
  "My friend just got Guitar Hero 3. I'll make him play bass."
  [Both laugh]
• After making statements indicating this person believes he actually is better than Tom Morello, "After you make Tom Morello or Slash your bitch, they play bass for you."

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chdir(2)
So today at work another developer many years my senior, with many more years experience than I, came to me with a Unixy problem.
"When I have a program, how can I have it so the current working directory for all processes it starts isn't the one that it started in?"
"chdir."
"No, I want so that if this process starts something like ls, when ls stats 'dot' I want 'dot' to be the directory that process wants it to be, not the directory that process was started from."
After about 15 minutes of me suggesting chdir while he said that's not what he wanted but then describing chdir, I finally wrote something along the lines of the following

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int
main (int argc, char *argv[])
{
  system("/bin/pwd");
  system("/bin/ls");
  chdir("/tmp");
  system("/bin/pwd");
  system("/bin/ls");
  chdir("/etc");
  system("/bin/pwd");
  system("/bin/ls");
  chdir("/");
  system("/bin/pwd");
  system("/bin/ls");
  return 0;
}

I compiled that, ran it, showed him the output. He said, "Yeah, that's what I want to do."
I showed him the code.
"chdir does that?"

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Alpha
Due to the power failure, there was the loss of several hours of work. Last night I installed FreeBSD 6.2-RELEASE on an old DEC AlphaStation 200 I have. I had started building a new, smaller kernel for it around 23:30 last night. It had not completed by the time of the power outage. I have restarted that build.
Any one reading this would reasonably ask, "Why are you not as confused/angry/annoyed with a compile that was not finished in 7 hours as you were about one that took 3 hours?"
The answer is simple. This AlphaStation is powered by a 100MHz DEC Alpha EV4 CPU and has 64MB of RAM. To the best of my knowledge, DEC made this machine around 1994 or 1995. I expected the build to take a long time; the machine is around a dozen years old.

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How long does it take to build a linux kernel?
It has been a number of years since I built a linux kernel. Slackware 9.1 was the last GNU/Linux distro I used before switching back to BSD. Tonight I put together a machine from some old parts (1.2GHz celeron with 256KB cache, 256MB RAM, 20GB hard drive) and installed Slackware 12. I customized a kernel configuration and attempted to build it. I don't remember the 2.4 kernel taking as long to build as this 2.6 kernel. It took nearly two hours. Granted, this machine is fairly old, but 2 hours? After I complete the tasks for which I needed this setup, I'm going to install an older Slackware with the 2.4 kernel and build that. I may also install FreeBSD and NetBSD and build their kernels. I'd like to get an idea how long it takes to compile other kernels on this rig.

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