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In some of my development and training guides, I like to use screen record and then post the videos online. It can show you rather than reading instructions,(as they say a picture says a 1000 words).

In doing so I use Ubuntu alot and find that a simple screen capture tool to use is XVidCap, this can usually be found in the repositories and can be installed.

Quick Tip:

On most of the installations, it has not worked, you press the record button and nothing happens. A solution to this is to add some different libraries, go to the Synaptic Package manger and install the libavcodec-unstripped-52 package, this should hopefully sort out the problem, also there have been reports of disabling the audio (not that I have found this feature yet)

Good luck

When I was first starting to use GIMP as a image editor it was full or pwerful features and for free. I was messing around and what I really needed to do was remove the white backround from images and make it transparent so I could use it in multiple instances on a website with different background.

This is a very simple approach and I am sure there are others, but this is how it do it:

1. Open up the imgae using the GIMP editor
2. From the menu select Layer -> Transparency -> Add Alpha Channel, You will notice that nothing happens, this is ok, it adds  transparency information to the layer
   1. Some images I find that Add Alpha Channel is greyed out, so use Delte Alpha Channel then redo the above step
3. Now, go to Select -> By Colour, then click on the white background in your image, you will see that it has selected all the white background area
4. To remove this and make it transparent, all you need to do is Edit -> Clear, you should now see that where the white background once was is now the grey tiles which show you it is transparent
5. Now Save your image

Any issues, or further suggestions, please let me know

Here is a screen movie of a simple task:

Okay, alot of out of the box php software packages (Wordpress, PHPBB, etc…) ask that mod_rewrite is enabled.

If you have just installed Apache through the package manager, you can quickly add the mod-rewrite module

In the terminal type this:

sudo a2enmod rewrite

Once you have done this, you will need to edit your virtual host files: To do this you can edit the file by typing:

cd /etc/apache2/sites-enabled
 
sudo gedit 000-default

make sure that where it says: AllowOverride None

you replace with AllowOverride All

Any issues, let me know

Okay, people trying to take shortcuts and give the /etc file directory full rights will find that Linux does not like this at all (I did it once…and never again)!

If you are having that propblem, you do not need to re-install (I use Ubuntu alot by the way).

First of all if you have this problem, the best way is to reboot and enter the GRUB (on Ubuntu this means pressing ESC at the start), then you should have a selection available to you, enter Rescue Mode (or Recovery mode), this gives you root admin access.

At the line prompt type:

chmod 0440 /etc/sudoers

You should then be able to reboot and all the settings are back.

Learn the lesson…..

As I have seen some really long winded ways of doing this, I thought I would make it easier by giving the following advice:

How to install a LAMP server on Ubuntu 9.04 and many other server configurations:

Open up terminal and type:

sudo tasksel

And then select the items you want to install and off you go

With the world of programming and application design taking off, I found one of the best ideas is to use Virtual Machines. I currently run VMware Player on Windows 7 and run a few Ubuntu VMs in it.

One of the issues I had starting was how to create a Virtual Machine without buying any software so here are the steps:

1. Download VM player from VMware – Click here
2. Now you want to get a virtual disk, if you have bought certain software you can make your own ones, or I have found a few on the net you can download, there is a good one at Forever for Now
3. I would suggest creating a directory at the high level for your VMs (make it easier), e.g. C:\vm
4. Copy the .vmdk file you just downloaded into this directory
5. Now you need a file that makes the VM work, this is a .vmx file, yet again without the software to make one you can copy and paste the below script into a text editor and save it as a .vmx file:<

   .encoding = "windows-1252"
   config.version = "8"
   virtualHW.version = "3"
   ide0:0.present = "TRUE"
   ide0:0.filename = "Ubuntu.vmdk"
   memsize = "1024"
   MemAllowAutoScaleDown = "FALSE"
   ide1:0.present = "TRUE"
    
   #ide1:0.fileName = "auto detect"
   #ide1:0.deviceType = "cdrom-raw"
    
   ide1:0.fileName = "D:"
   ide1:0.deviceType = "cdrom-raw"
    
   ide1:0.autodetect = "FALSE"
   floppy0.present = "FALSE"
   ethernet0.present = "TRUE"
   usb.present = "TRUE"
   sound.present = "TRUE"
   sound.virtualDev = "es1371"
   displayName = "Ubuntu"
   guestOS = "ubuntu"
   nvram = "Ubuntu.nvram"
   MemTrimRate = "-1"
    
   ide0:0.redo = ""
   ethernet0.addressType = "generated"
   uuid.location = "56 4d be 41 1b 4c 00 4c-82 9d cd 52 f9 ae 14 21"
   uuid.bios = "56 4d be 41 1b 4c 00 4c-82 9d cd 52 f9 ae 14 21"
   ethernet0.generatedAddress = "00:0c:29:ae:14:21"
   ethernet0.generatedAddressOffset = "0"
    
   tools.syncTime = "TRUE"
   ide1:0.startConnected = "TRUE"
   uuid.action = "create"
   checkpoint.vmState = ""
   tools.remindInstall = "FALSE"
   #gui.fullScreenAtPowerOn = "TRUE"
    
   extendedConfigFile = "ubuntu.vmxf"
    
   virtualHW.productCompatibility = "hosted"
   tools.upgrade.policy = "manual"
    
   vmotion.checkpointFBSize = "16777216"
    
   ethernet0.connectionType = "nat"
    
   usb.autoConnect.device0 = "path:1/4/2 autoclean:1"

6. Now you need to edit the line in the .vmx file

   ide0:0.filename = "Ubuntu.vmdk"

   To reflect the disk you have downloaded and placed in the vm directory.

7. Also read through the .vmx file and adjust any settings you think you need, for instance the memsize in the above example is 1024, you might want to increase or lower this depending on the size of your PCs RAM
8. After this you should now have a folder with the .vmdk file and the .vmx, you should now be able to double click on the .vmx file and this should boot into the Virtual machine through VMware Player
9. For those who want to get Ubuntu set up, download the latest ISO from the Ubuntu website and place it in the vm folder, then you need to edit the .vmx file, change the line

   ide1:0.fileName = "D:"

   to reflect the iso image, for example

   ide1:0.fileName = "ubuntu-9.04-desktop-i386.iso"

If you have any issues, please comment and I will aim to respond ASAP

Good Luck

Okay, for the three people who have asked me in the last week how to edit the JAVA_HOME variable here is the answer, oh and no it doesn’t matter if you are playing on a VM

In Ubuntu open up a terminal window,

The folowing command will let you know if you have a JAVA_HOME variable set, and it will show its location:

echo $JAVA_HOME

If nothing appears, you need to set the variable, and then the path, to do this you type the following (and remember to set the /examplepath to your java director, most commonly found in usr/lib/

JAVA_HOME=/usr/examplepath/java
export JAVA_HOME
PATH=$PATH:$JAVA_HOME/bin
export PATH