Note to self ...

And this may be interesting to other Science Fiction geeks out there. Pharyngula had a discussion regarding good Sci Fi and I want to hang on to it for a reference - lots of stuff I agreed with, so I suspect the books I have never read are worth checking out.

Science Fiction recommendations
Juvenile Science Fiction recommendations

And somebody also mentioned the SF Reviews site.

Installing Linux on antique hardware - Part 2

Fedora Core 3 did complete its install. BUT (and this is a big one) it doesn't appear to make it to the graphical login screen. The install took a good 2 hours, so by the time I finally got to boot, it was past midnight last night.

I'll give it another stab tomorrow. I may be able to telnet or SSH into the machine and correct stuff. Or I may not and may be off to do another try. But, tonight I have to work.

Installing Linux on antique hardware

This time I'm working on an install for an IBM Thinkpad 760XL for a friend at work who wants to impress his son.

Not sure on the CPU for this baby, but I think we've got a 2GB drive and 64MB RAM. This machine cannot boot from the CD drive... and the floppy and CD share a drive bay, so there is some juggling to do.

So far, I have successfully booted the CD. This took a bit, but I finally realized that Smart Boot Manager is capable of installing onto the boot sector of that hard drive. It also needs a bootable CD-ROM in the drive to show up in the menu. I had trouble with flopping the physical drives once it ran - not sure if that is a user error or a defect.

You'd think that that was the end of the story, but I Fedora Core 6 refused to allow me to install since I didn't have enough RAM to even get going.

I'm trying Ubuntu 6.06 right now, and we'll see how that goes.

If Ubuntu fails, I'm not messing around anymore and heading straight for Damn Small Linux.

UPDATE (11pm): Ubuntu kinda went off into la-la land and I ultimately tossed it. DSL does boot, but the graphical mode never comes up. If I need to go text-only, DSL is at least an option, but it was requested to go graphical. From a little further research and tinkering, I can get the FC1 installer to begin installing. I googled around a bit, and it appears that FC5 may also install with 64MB of RAM, so I will start working backwords. Bad news is that I need to download the FC5 CD's now.

Yum hosed?

Somehow 'yum' got into a perpetual state of not functioning within the last week. Not sure what preceded this, except I had trouble updating FC5 for about a week before it finally worked. I posted my question to FedoraForum and have a few suggestions, but I'm not above trolling for more assistance. :-)

Anyway, I've removed the MythTV repositories from the most-excellent Fedora Myth(TV)ology HOWTO but that doesn't seem to matter much at this point.

My working theory is that something in the extra repositories 'upgraded' the base Fedora installation and the conflict is giving yum fits. Unfortunately, the 'fit' is expressed as doing ... nothing. :-/

Backing up blogger (beta)

I upgraded this blog a few weeks ago, and forgot that my old automated script wasn't working very well. It is scheduled to run weekly, and it runs nearly forever after the upgrade. It also chews up over 4 gigabytes of space... no idea where it would stop since I typically find my Linux server is running slowly.

Anyway, I finally fixed up the backup script, and since I didn't find one quite like it, here it is:

cd `dirname $0`
TMP=/tmp/blogbackup
mkdir $TMP
cd $TMP

wget --progress=dot robgreene.blogspot.com
gawk '/([0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_archive.html)/ { \
      match($0, \
      "http://robgreene.blogspot.com/[0-9][0-9][0-9][0-9]_[0-9][0-9]_[0-9][0-9]_archive.html"); \
      print substr($0,RSTART,RLENGTH); }' <index.html >toget
wget --progress=dot --page-requisites --span-hosts --convert-links \
      -erobots=off --input-file=toget

cd -
tar czvf robgreene-blog-$(date +'%Y%m%d').tgz $TMP
rm -rf $TMP

Be careful of the word wrap.

Basically, I grab my index and then search for the monthly index links of the format ####_##_##_archive.html (# = digit). Once those are found, we download the monthly archives along with all of their images/css/javascript and other stuff.

Another visitor!

No, not the cousins. ;-)

Last night, the furnace was clunking a lot. We heard banging from - somewhere - in the basement. I finally headed down there with a flashlight and realized that something was caught in the furnace just in front of the air cleaner.

I came back down with a big garbage can, a stick, and big gloves. After turning off the furnace and the air filter, I opened it up and ... a flying squirrel?! Wow! It was pretty cagey, prowling around, but it wouldn't come by me.

I went upstairs to get my wife to standby (you know, just in case the thing jumped me) and went back down... the squirrel was now checking out the garbage can. One quick swoop and he was in the garbage can and I was hollering "open the garage door!!" Once I had a straight shot, I ran up and out. The poor fella was actually pretty cute. Don't want him inside though.

The good news? The furnace was nice an quiet the rest of the night.

The bad news? I bet we have a number of flying squirrels poking around. Boo!

Back to the compiler...

Building a compiler seems to be endlessly entertaining. There is always something to keep me busy - particularly so because I haven't really got a clue.

Here's one you may enjoy.

Working with a signed short, defined to be 2 bytes long, the range is -32768 (0x8000) to 32767 (0x7fff). What happens when you add one to the maximum value? How about subtract one from the minimum value? Multiply by 2? Divide by 2?

Simple, right? Well...

32767 + 1 = -32768
-32768 - 1 = 32767
-32768 * 2 = 0
-32768 * 3 = -32768
-32768 / 2 = -16384

Most of those should at least make you frown. It all makes sense and comes down to the fact that nobody wants to actually do a bounds check for every single computation done by a compiled program.

Starting with 32767 + 1. 32767 is, in hex 0x7fff, or 0b0111 1111 1111 1111 (binary). Add one to that, and you get 0b1000 0000 0000 0000. The high bit in a signed operation means negative. We just flipped from positive territory into negative territory. 0x8000 is the same value as -32768. Run that in reverse for -32768 - 1 becoming 32767.

-32768 * 2 is, essentially a bit-shift to the left. So, -32768 = 0x8000 = 0b1000 0000 0000 0000. Shifting the bit pattern to the left one bit yields 0b0000 0000 0000 0000, and this is easy, that is 0x0 or 0. Times three is the same as -32768*2 + -32768*1, so, by substitution, that becomes 0 + -32768*1, or -32768 (again the "times 2" part is shifted out of our value).

-32768 / 2, comes out right simply because dividing comes down to shifting to the right. So, 0b1000 0000 0000 0000 shifted to the right becomes 0b1100 0000 0000 0000 (the high bit is replaced), and we get the right answer of -16384.

Cool, huh? Real numbers have similar "gotcha's" that also make sense with a little thinking.

I am so ashamed

I am so ashamed at the state of Wisconsin. We have allowed the hatred and bigotry of the majority to, essentially, dehumanize our fellow citizens.

Do you think homosexuals are incapable of forming a lifelong bond? Of course not. Do they have the same concerns about protecting each other throughout their lives? Of course they do. Do we judge any marriages within the law? Of course not. Should we infringe on the freedom of anybody because we don't like "them"? Absolutely not.

So, somebody, please explain rationally why they are not afforded the same protections the rest of us are, because I just don't see it. All I hear is FUD.

Shame on you.

What really bothers me...

Is that we have the opportunity to vote about what some one else is allowed to do. This is an activity that has no connection to the voters. Nobody gets hurt. The people in involved are both consenting adults. And, yet, because the group of people is a minority, we can disallow them from doing something.

I think that's why this gay rights deal really hits home.

I'm a left handed person - maybe all the "righties" should get together and disallow me from doing something innocuous? Same difference.

I got a letter...

One of my coworkers today was wandering around asking people if they had gotten a certain letter. It was a letter about gay marriage from a friend of mine - who happens to be gay. This coworker was confused why he seemed to be singled out. Well, he wasn't. I got one too!

The letter was well written. I cannot even conceive of how difficult a decision it was to write the it in the first place. With todays religiously motivated society, that takes guts.

The whole concept of "banning" gay marriage is ludicrous. This is just another wedge issue for Republicans. I really and honestly believe that, since their entire platform seems to be primarily one of fear and hate.

Anyway, anyone who knows me knows how I'll vote. And, as my coworkers will attest, I'm willing to argue with anyone about this.

Freedom is always a struggle.