Tuesday, 24 July 2007

Installing stellarium on Ubuntu 7.04

Stellarium is one of the best planetarium programs I have seen and the best of all is that it is free and open source!

To install this gem you must run the following command :
ubuntu@horus:~$ sudo apt-get install stellarium stellarium-data
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
libsdl-mixer1.2 libsmpeg0
The following NEW packages will be installed:
libsdl-mixer1.2 libsmpeg0 stellarium stellarium-data
0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.
Need to get 16.2MB of archives.
After unpacking 22.6MB of additional disk space will be used.
Do you want to continue [Y/n]? y
Get:1 http://ar.archive.ubuntu.com feisty/main libsmpeg0 0.4.5+cvs20030824-1.9build1 [102kB]
Get:2 http://ar.archive.ubuntu.com feisty/main libsdl-mixer1.2 1.2.6-1.1build1 [136kB]
Get:3 http://ar.archive.ubuntu.com feisty/universe stellarium-data 0.8.2-3 [14.2MB]
Get:4 http://ar.archive.ubuntu.com feisty/universe stellarium 0.8.2-3 [1809kB]
Fetched 16.2MB in 2m17s (118kB/s)
Selecting previously deselected package libsmpeg0.
(Reading database ... 116812 files and directories currently installed.)
Unpacking libsmpeg0 (from .../libsmpeg0_0.4.5+cvs20030824-1.9build1_i386.deb) ...
Selecting previously deselected package libsdl-mixer1.2.
Unpacking libsdl-mixer1.2 (from .../libsdl-mixer1.2_1.2.6-1.1build1_i386.deb) ...
Selecting previously deselected package stellarium-data.
Unpacking stellarium-data (from .../stellarium-data_0.8.2-3_all.deb) ...
Selecting previously deselected package stellarium.
Unpacking stellarium (from .../stellarium_0.8.2-3_i386.deb) ...
Setting up libsmpeg0 (0.4.5+cvs20030824-1.9build1) ...

Setting up libsdl-mixer1.2 (1.2.6-1.1build1) ...

Setting up stellarium-data (0.8.2-3) ...
Setting up stellarium (0.8.2-3) ...

After that I ran the stellarium but it started in an invalid screen resolution
so I had to edit its config file :

gedit /home/ubuntu/.stellarium/config.ini

Then I modified the screen resolution, because I use 1400x1050.
So I changed the following lines :
screen_w = 1024
screen_h = 768

for :
screen_w = 1400
screen_h = 1050

Afterward I ran again the stellarium with the command :

The basic operations are :
Use the mouse or arrow keys to look around.
Use the page up and page down keys to zoom in and out.
Use the left mouse button to select an object, the right button to deselect the object and middle mouse button or spacebar to center on the selected object.
J slows down or reverses speed, L increases time speed, and K makes time return to normal speed.
You can also use the time control buttons in the lower right of the screen.

It runs on Mac and Micro$oft Window$ too!

I strongly recommend this software.

Tuesday, 17 July 2007

Asa Dotzler conference in Buenos Aires - Argentina

Last July 3rd I went to a conference by Asa Dotzler about Firefox.
The meeting took place in "La comedia" Theatre - Rodriguez Peña 1062 from 11:30am to 14hs It was organized by "Comunidad Mozilla Argentina" and "Comunidad de Software Libre de Argentina". It was very interesting to listen to Asa Dotzler.

For those who don't know who Asa Dotzler is, he is a co-founder and community coordinator for the Spread Firefox project, launched in October 2004, where he spearheads open source marketing projects.Dotzler has been an active member of the Mozilla community since 1998. After volunteering for more than a year, Dotzler joined the Mozilla organization, and has played a key role in delivering products including the release of Mozilla 1.0 and
the release of the Mozilla Firefox web browser and Mozilla Thunderbird e-mail and usenet client.

Asa started by explaining about mozilla, and the firefox numbers :

* 100+ Millon users worldwide
* 2.500+ community-contributed extensions
* 41 languages (and growing)
* 16% Worldwide market share
* 1,600+ contributors to code base
* thousands of volunteers & evangelist
* fewer than 100 employees

He explained the global usage of firefox and the security related issues in every browser. He remarked the importance of how much time the programmers needed to fix a bug. He said something that I completely agree with : that every software has bugs, and the problem is how long you take to fix them.

*In 2006 Firefox users were at risk for 9 days
*MSIE & MSIE-Based browser users at risk for 284 days.

Then he talked about the importance of the community that helps firefox, more than 1600 programmers, more than 10000 testers every night and more than 500000 beta testers around the world! and how they organized all these people.

At last he spoke about What's Next :

*Graphics - Cairo
*FUEL (Firefox User Extension Library)
*Malware protection

In the end of the conference he answered a few questions from the public.

My impression was that Asa is a very modest and smart guy. I was happy to meet him in such a geeky atmosphere.

I have to say that M$ Internet explorer 7 deliberatly copied the tab browsing of Firefox.Just like other Micro$oft "innovations", they unabashedly copy someone else's program and relaunch it, but of course in a Micro$oft-Way (Bugs, Unsecure, Privacy monitoring, etc) A good example are Vista's Gadgets being just a bad copy of "Yahoo Widgets" or the Xbox being a bad copy of Playstation... just to name a few...

I strongly recommend using Firefox. Even aliens use it!!!

See it usign Google Maps :
Firefox Field

And don't forget to check the Mozilla Foundation:

"The Mozilla project is a global community of people who believe that openness, innovation, and opportunity are key to the continued health of the Internet."

Thanks Asa for your visit!!!

Monday, 16 July 2007

Running Windows XP under Ubuntu with VirtualBox

A few weeks ago I installed another virtualization product under linux. It's name is VirtualBox
I have been using VmWare but I decided to use an open source virtualization tool. So I found VirtualBox that is freely available under GNU General Public License (GPL).

According to its site :
VirtualBox runs on Windows, Linux and Macintosh hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista), DOS/Windows 3.x, Linux (2.4 and 2.6), and OpenBSD.

After reading the site I understand that there are two versions, one open source with GPL license and one in binary format with an installer and a PUEL license

First I downloaded the file
from the site :

After the download was complete I ran the command :
sudo dpkg -i virtualbox_1.4.0-21864_Ubuntu_feisty_i386.deb

Then it appeared in the menu Applications->Systems :
InnoTek VirtualBox

Afterwards I allowed my user to run virtualbox.
I went to the menu System->Administration->Users and Groups
Clicked on "Manage Groups" and added my user to the group "vboxusers"

I rebooted and afterward I launched the VirtualBox application and pressed the New Button and followed the wizard.
I created a 5 gb disk and a virtual PC with 256MB ram.
I enabled the cdrom drive and inserted the Windows XP that came with the laptop in the cd-rom drive.
Before starting the virtual machine I changed the "Host key" because the default is the right ctrl, but my laptop doesn't have a right-ctrl.
So I selected the menu File->Global Settings and then in the Input option I changed it for the left ctrl (Control_L).
Afterward I started the virtual machine and the Windows XP installer appeared.

If I moved the mouse over the virtual machine window it captured your mouse, to get out I pressed the "host key".

Windows XP was installed with only 800x600x32 bits screen resolution. To have a better resolution I installed the guest add-on (In the running virtual machine window I selected devices->Install Guest Additions).
After that in my case I was able to select 1400x1050x32bits.
And then when I moved my mouse over the virtual box window it captured the mouse, but if I moved the mouse away it freed the control (without need to press the "host key").

I was able to surf the web inside XP, but I want to share a folder between both operating systems so I opened a terminal in ubuntu and ran the command :

VBoxManage sharedfolder add Virtual_Machine -name "sharedfolder" -hostpath "/foldertoshare"

Virtual_Machine : is the name of the virtual machine. Mine is "Windows XP".
sharedfolder : is the name of the resource to be used in the "net use" command under Windows.
foldertoshare : is the name of the folder in ubuntu that you want to share.

Here is the command I used :

ubuntu@horus:~$ VBoxManage sharedfolder add "Windows XP" -name discoD -hostpath /diskD/

I exited the terminal started the virtual machine and after I was logged in windows XP I ran :
net use Z: \\vboxsvr\discoD
Then I was able to share data with my ubuntu.
Here a Picture with the net use command :

Monday, 2 July 2007

Using a file as a Swap Partition for Ubuntu

I have one internal hard disk in my laptop Compaq Presario 1500 with 4 partitions
XP, Ubuntu, Solaris 10, Pc-BSD. So I can't create another partition to use as a swap for Ubuntu. But I have one large external hard disk connected by USB, so I used a file in this disk as a swap partition.
First I created a 1GB file in the disk (already mounted as /diskD/) :

sudo dd if=/dev/zero of=/diskD/swapubuntu bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 86.4074 seconds, 12.4 MB/s

Afterwards :
sudo mkswap /diskD/swapubuntu
Setting up swapspace version 1, size = 1073737 kB
no label, UUID=6da4119f-3329-4935-a921-10a5cbe521be

Then :
sudo swapon /diskD/swapubuntu

Then just to check I ran the following command :
total used free shared buffers cached
Mem: 515852 509052 6800 0 100460 170968
-/+ buffers/cache: 237624 278228
Swap: 1048568 0 1048568

In order to have the swap activated in every reboot I modified the file /etc/init.d/rc.local
sudo gedit /etc/init.d/rc.local
Adding the following line :
swapon /diskD/swapubuntu
Here my rc.local :

#! /bin/sh

[ -f /etc/default/rcS ] && . /etc/default/rcS
. /lib/lsb/init-functions

do_start() {
if [ -x /etc/rc.local ]; then
log_begin_msg "Running local boot scripts (/etc/rc.local)"
log_end_msg $?
swapon /diskD/swapubuntu

case "$1" in
echo "Error: argument '$1' not supported" >&2
exit 3
echo "Usage: $0 start|stop" >&2
exit 3