Zhixian's Tech Blog


Goam for Ubuntu 10.04

Filed under: computing, web application development — Tags: , , , , — Zhixian @ 03:53:07 am

If you were trying to learn Objective-C on Ubuntu, chances are that you will try and install the GNUstep development package.

Unfortunately on Ubuntu, when you try to install that package (using Synaptic Package Manager), you will receive an error that says:

Depends: gorm.app but it is not installable

What is this Goam.app thingy? Well, it simply the Visual Interface Builder for GNUstep

In any case, to fix this problem, you first have to download the appropriate goam package from:
For me the right package is gorm.app_1.2.10-1_i386.deb

After you download and install that package, you should be able to install the gnustep-devel package to continue your way to learning about Objective-C.


Ubuntu Software Center

Filed under: computing — Tags: , , — Zhixian @ 12:05:07 pm

If you already have an idea of the what is the name of the software that you want to install, you could try using Ubuntu Software Center to install the software instead of using Synaptic Package Manager. It really is a much more user-friendly interface to install software packages.

Set MySql default collation to UTF8

Filed under: computing, database, web application development — Tags: , , , , , , — Zhixian @ 02:06:07 am

One of the bad thing about installing MySql using Ubuntu Software Center is that it does not allow you to select the default collation of MySql Server. This is one of the nice things you would find in the Windows version of MySql installer.

In any case, to set MySql collation to use UTF8, all you have to do is:

  1. Edit your MySql configuration file (typically found at /etc/mysql/my.cnf)
  2. Under the section [mysqld]add the following lines:
    # utf8
    init-connect=’SET NAMES utf8′
  3. Restart your MySql


Accessing a Windows machine via Remote Desktop Protocol

Filed under: computing — Tags: , , — Zhixian @ 02:02:07 am

Yes. Using RDP. Not VNC. Not SSH. RDP!

On Ubuntu terminal type:

rdesktop xxx.xxx.xxx.xxx

where xxx.xxx.xxx.xxx is the IP address of the machine that you are trying to access

You can learn more from this post: http://ubuntuforums.org/showthread.php?t=824710


Loading ISO images

Filed under: computing — Tags: , , — Zhixian @ 03:46:07 am

The user friendly way to load (or mount as they say it in Linux terminology) an ISO image, is to right-click the ISO file, and select the option Open with Archive Mounter

This will load the ISO image, and an icon resembling a hard-disk with the filename of the ISO file will appear on your desktop

I’m really loving this Ubuntu Linux more and more.

Creating ISO from CD/DVD using Brasero

Filed under: computing — Tags: , , — Zhixian @ 03:40:07 am

Just found this out.
There’s actually an easier (and more user-friendly) way to create ISO images in Ubuntu.
As it turns out Ubuntu include Brasero, a free disc-burning program as part of its distribution.
So you can actually use this application to create ISO images, instead of mucking around the command-line.

When you insert a disc in Ubuntu, it will auto-mount the media and an icon representing the mount-point of that media will appear on the desktop.
To create the ISO, just right-click the icon and select the option Copy Disc…
A dialog will appear requesting you to select the disc to copy and to select the disc to write to.

In the option of selecting the disc to write to, select Image File in the drop down list.

The default format is Brasero’s .TOC (CD-R/Disc-At-Once) format which is not the ISO9660 format that we want.

So to get that, click on the Properties button.

A dialog will popup. In this dialog, there is an option labeled Disc image type.
Click on the drop-down list and select ISO9660 image to create ISO images.

Close the dialog (by clicking on the Close button) and then click on the Create Image button to begin creating the ISO.

Creating ISO images from CD/DVD

Filed under: computing — Tags: , , — Zhixian @ 03:01:07 am

I was trying to find out how to make ISO images from a CD/DVD where I came across this from Lifehacker:

Note:You cannot create an ISO from a mounted media.
You need to unmount it first. Ubuntu auto-mounts all media so you need to execute the following command to unmount it:
sudo umount /dev/cdrom
Turn a CD/DVD into an .iso
dd if=/dev/cdrom of=file.iso bs=1024
Turn a folder into an .iso
mkisofs -r -o file.iso /location_of_folder/

Generate an MD5 checksum file
md5sum file.iso > file.iso.md5


Using Personal Package Archive (PPA) in Ubuntu

Filed under: computing — Tags: , , , — Zhixian @ 02:13:07 am

Some preamble on what are PPAs

PPAs or Personal Package Archives are software packages generated by individuals that not checked or monitored. You install software from them at your own risk. That is to say, one should only install PPAs from individuals or organisations that they trust.

While trying to find a decent offline-blogging client tool that would support Windows Live Spaces, I read that BloGTK is a tool to try. So, I fired up my Synaptics Package Manager (SPM), do a search for “blogtk” and installed it.

Unfortunately on Lucid Lynx, I found that it refuses to start up. It would start and then mysteriously closes.

I went to the author’s site and read that the author has released a newer version on his repository. Unfortunately, this newer version is not available yet on the default software repositories that my Synaptics Package Manager is connected to. Which means if I want to use it on Lucid Lynx I have to add the author’s repository to SPM.

Luckily this is quite simple to do. Things to note: the PPA in question. In this case, the PPA for BloGTK happens to be ppa:jayreding/ppa. So on your terminal, punch in the following commands:

Add repository
sudo add-apt-repository ppa:jayreding/ppa
System will now fetch the PPA’s key. This key allows system to verify that the packages in the PPA have not been interfered with since they were built.

Update the package list from repository
sudo apt-get update
System will now look at available packages on the PPA and add them to the local repository packages list.
After this is done, you can fire up SPM again and search for “blogtk”. You should be able to see the newer version there. Installed it and you should be able to use BloGTK to write your blog posts.

Enabling user directories on Apache

Filed under: computing — Tags: , , , — Zhixian @ 01:32:07 am

To enable user directories on Apache, follow the following steps:

Go to Apache’s enabled modules directory. The default directory location should be “/etc/apache2/mods-enabled”:
cd /etc/apache2/mods-enabled

Create symbolic links from mods-available to mods-enabled directory using the following commands:
sudo ln -s ../mods-available/userdir.load
sudo ln -s ../mods-available/userdir.conf

Restart Apache:
sudo apache2ctl restart
At this point, user directories should be enabled. To test it out perform the following steps:

Go back to your user directory and create a folder named “public_html” cd\
mkdir public_html

On your browser navigate to the location “http://localhost/~username“. For example, since my username is “zhixian”, I would type the following as URL in my browser: http://localhost/~zhixian/
Since the public_html folder is empty, you will get an empty directory listing. Add a “index.html” file to set the initial content.

Notes on Apache server

Filed under: computing, Uncategorized — Tags: , , — Zhixian @ 01:20:07 am

A few things to note for Apache server:

The default document root directory is:

The default installation directory is:

The main Apache server configuration file is located at:

Blog at WordPress.com.