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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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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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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Fun little alias
I use a console based RSS reader written in Ruby. It crashes often and will delete my list of feeds in the process. It also has a tendency to not fully exit, leaving a ruby process sitting in the background soaking up close to 100% CPU time. For such occasions, I've added the following alias to my .cshrc file.

alias killraggle kill -9 '`ps ax|grep raggle|grep -v grep|awk '\''{print $1;}'\''`'

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