Techno Thoughts!

If you use VirtualBox and try to copy/clone a hard disk (VDI) file to use with another virtual machine, it will not let you add it because it complains that there is already an image with that UUID.

Fortunately the fix is simple - there is a hidden command available to generate a new UUID:

VBoxManage internalcommands setvdiuuid myfile.vdi

To recursively chmod all files in the current directory (and sub-directories), you can do this:

find . -type d -exec chmod 755 {} \;

To do the same with just files, you can use:

find . -type f -exec chmod 644 {} \;

It’s really useful to not only be able to see the user and directory in your prompt but to have different colours for different users/servers - like a different colour for root or production boxes. Here is the code I use - just put it in a .profile in the users’s home directory (or in /etc/profile for globally):

# Set xterm title:
SHOSTNAME=`hostname -s`
PROMPT_COMMAND='if [ "${TERM}" = "xterm" -o "${TERM}" = "xterm-color" ];
then
   if [ -n "${XTITLE}" ];
   then
      echo -ne "\033]0;${XTITLE}\007";
   else
      echo -ne "\033]0;[${USER}@${SHOSTNAME}:${PWD}]\007" | sed -e "s@${HOME}@\~@";
   fi;
fi'    

# Set Bash Prompt:
if [ "$BASH" ]; then
  PS1='\[\033[1;36m\][\u@\h:\w]\$\[\033[0m\] '
#  alias ls='ls --color'
else
  if [ "`id -u`" -eq 0 ]; then
    PS1='# '
  else
    PS1='$ '
  fi
fi  

export PS1 PROMPT_COMMAND SHOSTNAME

You can change the colours using the following codes:

# Black       0;30     Dark Gray     1;30
# Blue        0;34     Light Blue    1;34
# Green       0;32     Light Green   1;32
# Cyan        0;36     Light Cyan    1;36
# Red         0;31     Light Red     1;31
# Purple      0;35     Light Purple  1;35
# Brown       0;33     Yellow        1;33
# Light Gray  0;37     White         1;37

If you have a high load on your web server, it’s useful to be able to see a list of the current connections on port 80 as sometimes high load can be caused by someone abusing the site - for example scraping it or some kind of denial of service attack.

This code will show a list of the ip’s currently connected to your server on port 80 with a count of the number of connections to the left of it. It’s ordered by the number of connections - highest first:

netstat -ntulpa | grep :80 | awk '{print $5}' | cut -d: -f1 | sort -n | uniq -c | sort -n -r

I mentioned in a previous post that you could call 0800 numbers free from a mobile using a free service provided by Localphone.

They have now released another free service which gives free, quick and easy conference calls: ConferenceBuster.

If you want to have more than 1 person on a call to someone, all you do is go to: http://www.conferencebuster.co.uk, click the button and it gives you a phone number and pin.

You give the other person the phone number and pin and dial it yourself.

It’s free and the number to dial is a normal 01xxx number so will come out of your free minutes on your mobile for example.

Came across a very nifty utility for web developers - it’s called IETester.

It’s a web browser which allows you to open up different tabs for different versions of Internet Explorer all at the same time.

You can view IE 5, IE6, IE7 and IE8.

It seems to fall down with some complicated Javascript but it’s great for testing how a site renders in the different versions or as usual, sorting out IE6 problems!

It’s freeware and you can download it here.

Apple just announced the new ‘iPhone 3G S’ at it’s WWDC 2009 conference.

The S stands for ‘Speed’ and the new iPhone will contain the following new features:

• Faster
• 3 mega-pixel camera with auto focus and auto macro
• Video recording and editing
• Voice commands
• A digital compass
• Improved battery life

The exterior of the device will be the same as the current iPhone 3G.

Apple today confirmed, at it’s WWDC 2009 conference that the previously announced 3.0 firmware that has been in beta for the last few months will be released on June 17th.

The update contains many big features such as Copy & Paste and MMS but also includes 100 updates and 1000 new API calls.

Many years ago I remember that 0800 numbers were free to call from mobile phones as well as land lines. That all changed a long time ago though and 0800 numbers are chargable calls - which is annoying when most phone call packages come with plenty of minutes nowadays.

Here is a neat trick though to be able to call 0800 numbers using your inclusive minutes.

1. Go to 0800buster.co.uk

2. Note the number in the top left hand corner of the page (this is randomly displayed from their pool of numbers so if one doesn’t work, just refresh and try another!)

3. Store it in your mobile for when you need to dial an 0800.

To call an 0800 you can now call that 0800buster number and enter the 0800 you would like to call, followed by #

You can even store numbers in your phone book by using the pause function on your mobile - see the 0800buster site for details

There have been several rumours recently about the spec of the next, rumoured iPhone.

The Apple iPhone Apps site has given a good roundup and review of them - see here. All sounds plausible to me - certainly along the lines of what I was thinking!

* 32GB and 16GB to replace current capacities
* $199 and $299 price-points to be maintained
* 3.2 Megapixel camera
* Video recording & editing capabilities
* Ability to send a picture & video via MMS
* Discontinuation of the metal band surrounding the edge of the device
* OLED screen
* 1.5X The battery life
* Double the RAM and processing power
* Built-in FM transmitter
* Apple logo on the back to light up
* Rubber-tread backing
* Sleeker design
* Built-in compass
* Revolutionary combination of the camera, GPS, compass, and Google maps to identify photo and inform about photo locations.
* Turn by turn directions
* July 17th, 2009 release date

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