October 2009
19 posts
2 tags
“Perkele!!! Our dog had made a big poo on the floor during the day. Next, our...”
– Petteri Hiisila
1 tag
Fixed Mindset vs. Growth Mindset: Which One Are... →
2 tags
Shell-Scripting for Fun and Profit: Finding,...
Motivation
Professors often provide a page with links to lecture slides in PDF format. The main benefit of joining them to a single document, is that one can use a reader’s search function to find topics and keywords faster than when searching in multiple documents.
The Script
Change the URL variable to the page with links to lecture slides. Edit the grep and pdfjoin lines to match...
1 tag
WatchFrom BBC: Undercover: Hate on the Doorstep.
5 tags
Real VMX QEMU Script →
A script for people who want to develop for Real VMX, a VxWorks-like operating system kernel. The script installs ext2, GRUB, and a vanilla kernel to a small (32 MiB) QEMU image.
Some features of Real VMX:
Priority-based multitasking and round robin scheduling
Partition-based memory management
Binary and counting semaphores with priority-inheritance
Message queues for inter-process...
2 tags
“Reading about how to avoid procrastinating is amongst my very favourite ways of...”
– Greg Detre
Kid's Corner: Learning Computers and Development... →
3 tags
The Use of “do { … } while (0)” in C Macros
Consider a countdown program.
countdown.c:
#include <stdio.h>
#include <unistd.h>
int main(int argc, char **argv)
{
int seconds = 3;
for (int i = seconds; i != 0; --i) {
printf("%i... ", i);
fflush(stdout);
sleep(1);
}
puts("Go!");
return 0;
}
The goal is to put the actual countdown code in a macro. It fits perfectly in a function,...
1 tag
Introducing the Internet to People
I remember being given step-by-step instructions how to use websites to solve tasks. Frustration arose, the same kind generated from having to read a technical manual. People prefer to play around with things. When introducing computer based problem solving to people, hints and startings points are enough. If the information is relevant, they might use it. If not, googling will get them started....
3 tags
Reddit: How To Beat Procrastination, by Djork →
I will try this out some time.
3 tags
The Wiki Reader →
4 tags
Using Javascript to Provide Dynamic Content in...
This article describes how content can be added to Tumblr using Javascript, and the jQuery library. The reader should be familiar with web development.
A Simplified Theme
<html>
<head>
<title>My Tumblr</title>
<script type="text/javascript" src="http://example.org/jquery.js"></script>
<script type="text/javascript"...
2 tags
10/GUI: A Multitouch Interaction System →
4 tags
Configuring an SSH Gateway
An SSH gateway can be used where multiple hosts share the same IP address, where it isn’t possible, or acceptable, to use separate ports for the hosts’ SSH daemons.
Consider the following network,
where Alice and Bob both need to work with two servers, on the same external IP address, and a restrictive firewall (or sysadmin) that refuses to open non-standard ports for the...
4 tags
How to Include Reddit in Tumblr
I wanted to include a reddit widget in my posts, in order to submit and vote on entries. Here’s a theme snippet that solves the task:
<script type="text/javascript">
reddit_url = "{Permalink}";
</script>
<script type="text/javascript" src="http://www.reddit.com/button.js"></script>
Put in a simplified tumblr theme:
{block:Posts}
{block:Text}
...
1 tag
NY Times: Fox’s Volley With Obama Intensifying →
3 tags
Enabling NTP in OpenBSD
The system clock in my Sun Ultra 5 drifted away every few days. This is how
NTP is enabled in OpenBSD:
$ sudo su -
# echo 'ntpd_flags=""' >> /etc/rc.conf.local
This will cause the ntpd daemon to be started next time you reboot the system. To start it right now, do:
$ sudo ntpd
Last, to make sure the daemon is running correctly, examine the contents of /var/log/daemon:
$ sudo su -
#...