MonthOctober 2005

Komodo with Ruby support

By the way… I started looking into ruby a while ago (after checking out what all the fuss concerning ‘Ruby on Rails’ was all about and being pleasantly surprised by both Rails and Ruby).

Now, seeing that Activestate Komodo is my favorite tool for both perl and php (it even works on both windows AND linux… and even mac os x, but I don’t use os x (yet)), I was pleasantly surprised (again) to see the next version would have ruby support.

Check the beta/alpha here.

Installing scons on Fedora Core 3

I downloaded the rpm scons-0.96.1-2.1.fc3.rf.noarch.rpm from http://dag.wieers.com/packages/scons/

If scons (I needed it for the kdissert mind mapping tool), gives the following error:

Checking for uic : uic was not found - set QTDIR put it in your PATH ?


You probably need to install the Qt gui toolkit headers with ‘yum install qt-devel’

If you get:

Checking for the kde includes : The kde includes were NOT found

You need a ‘yum install kdebase-devel’ (or at least something else this is dependent on)

Hope this help someone some minutes googling or maybe prevents some hairpulling. In any case, kdissert is a nice tool though. I was just evaluating a commercial mindmapper on windows (Visual Mind) when it caught my eye. It’s got basically the same features so I guess I can stop evaluating it. I must admit Visual Mind looks real nice, but my wallet can’t see the difference.

I just wonder… why is it you can’t have 2 branches arrive at the same node… say, you’ve got 2 possible paths giving the same result and you haven’t made up your mind yet about which one you’ll be using. This doesn’t seem to be possible in either kdissert or Visual Mind.

FXRuby – require keeps returning false

You installed the fxruby gem, installed the FOX GUI library, checked dependencies, compiled and rechecked everything several times again, breaking your head why the ‘quick sanity check’ (require ‘fox14’) as suggested on http://www.fxruby.org/doc/gems.html keeps returning ‘false’ ?

Well, instead of:

require 'rubygems'
require 'fox14'

try this:

require 'rubygems'
require_gem 'fxruby'

Supposedly both should work, but somehow only the ‘require_gem’ way works for me.

…I hope this saves some people some headaches…

Problem booting copied Fedora partition with Grub

Situation:
After copying a Fedora Core 3 partition to a new harddrive (using Knoppix) I was at first unable to boot the new partition (using Grub).
I got the following error:

switchroot: mount failed: 22
umount /initrd/dev failed: 2
Kernel panic - no syncing: Attemped to kill init!

I vaguely remembered having this situation before, but really couldn’t remember how I dealt with it.
Googling around didn’t really produce much results at first (only more people having the same issue, but no real answers), but I was able to puzzle a solution together.

Problem:
It turned out that both my grub.conf and /etc/fstab files contained a reference to a ‘LABEL’ that seemed to be missing. Relevant entry of grub.conf:

title Fedora Core (2.6.9-1.667)
root (hd0,5)
kernel /boot/vmlinuz-2.6.9-1.667 ro root=LABEL=/ rhgb quiet
initrd /boot/initrd-2.6.9-1.667.img

entry of fstab:

LABEL=/ / ext3 defaults 1 1

Solution:
For as far as I understand you’d normally put a device here (in my case I would have been able use /dev/hda6 in both files), but the ‘LABEL=/’ here means as much as ‘use the partition with label /’.
Putting a label on a partition is possible using ‘e2label’. I labelled my /dev/hda6 as follows (using Knoppix):

su
mount -o dev,rw /mnt/hda6
(to mount my new partition writable)
e2label /mnt/hda6 /

Apparently it’s also possible to set the partition label/volume name using ‘tune2fs’, but since the above worked for me I didn’t really look into this.

Dew-NewPHPplinks category insert made easier

A while ago a friend of mine wanted to run an ‘internet directory’ using a php/mysql based script called Dew-NewPHPLinks.

He wanted to add a whole bunch of categories but the online standard way to do this really is a bit cumbersome to add more than a handfull at a time. I helped him out by writing a little php script that adds categories from a txt file with a fairly straightforward layout.

You can find the script here.

I really can’t remember the exact purpose of formatting/parameters, but the script itself contains a little example commented in which I remember was straightforward at the time.

Remember to change the path to your categories-textfile and your mysql connection parameters as needed.

Aloha!

…and welcome to my (=Piet Hadermann) ‘blog’.
Well, actually… I’m planning on using this more as an automated notepad to preserve various notes (probably all IT/development related, since I don’t usually keep notes concerning anything else) for the future.

I tended to keep notes on paper. Although paper has some big advantages (extreme portability, low power requirements, really nice tactile user interface) I was always unable to find the notes I needed later on. Unfortunately Google also turned out to be unable to index my notes. I guess their bot was unable to decipher my handwriting or decided it was spam.

I also use a ‘private’ wiki for various notes and brain-dumps, but as from now on I’m planning on dumping any info that might benefit someone else right here.

In the past I’ve often stumbled upon blogs and web pages of people doing just this when I was looking for a way to solve a problem or some information. This is my way of giving something back without really having to put in any extra effort (I especially like the ‘no extra effort’ part).

blahblah yadayada and so on… (you should really get a hobby if you’ve read this far)