The Mistake:

1. Single user mode: i am the only system user and i and the admin
2. Wanted to add myself to the vbox group
3. My supplementary groups were “admin” which is the Ubuntu default for superusers
4. typed the command usermod -G vboxsf naveen ( missed the -a Flag )
5. The correct command must have been  usermod -aG vboxsf naveen (the -a appends )
6. Without the -a flag, my supplementary group got overwritten as vboxsf – and now i dont have admin privileges – duh!!

The recovery:

1. Reboot into Ubuntu
2. Press and Hold the “Shift” button to access the GRUB
3. From the GRUB select Recover Mode
4. You should see a window with 4 options (resume, fsck, remount, root)
5. Select remount – it will remount the file system as read write
6. The file system during recovery mode will typically be mounted as read-only – so you cannot modify anything if you dont do the above step
7. Next select root: Drop to root shell prompt, it will drop you into the root command prompt
8. Now you are root and can do anything
9. I fixed my error with usermod -aG admin naveen ( no typos this time ! )
10. Exit-Reboot and you are fine !!

Its amazingly fast and has a very simple interface

To install Xfce on Ubuntu do the following

sudo aptitude update && sudo aptitude install xubuntu-desktop

Log out and select Xubuntu or Xfce

To get dual monitors to work with Xfce you can do the following

• Go to Start > Settings > Settings Manger > Display
• 2 monitors must be displayed there
• Click on each monitor and make sure both are in use
• “Use this Output” checkbox must be checked in both
• Open a terminal and type xrandr 
• Output should be similar to this

Screen 0: minimum 64 x 64, current 1680 x 986, maximum 32000 x 32000
VBOX0 connected 1680×986+0+0 0mm x 0mm
1680×986 60.0*+
1280×960 60.0
1024×768 60.0
800×600 60.0
640×480 60.0
VBOX1 connected 1680×986+0+0 0mm x 0mm
1680×986 60.0*+
1280×960 60.0
1024×768 60.0
800×600 60.0
640×480 60.0

• On the terminal type xrandr –output VBOX0 –left-of VBOX1
• change –left-of to –right-of for other option
• This should show the 2 monitors – but you will have to do it every time you log in
• So make a startup command
• Go to Start > Settings > Settings Manger > Session and Startup
• Application Startup Tab > Add 
• In the command box, enter the exact command you did above ( for me it is xrandr –output VBOX0 –left-of VBOX1 )
• See Pic below

• There is also a graphical interface for doing this called grandr
• You can install it by using sudo apt-get install grandr
• Go to the terminal and type grandr
• A small window must popup and you can do the changes

PHPStorm is a nice ( but not free ) IDE  and we decided to use it in our development environment.
Installs nicely in Windows and Mac.
However, Ubuntu 11.10 is the problem as it does not have SUN JDK by default.

Requirements:

1. Ubuntu 11.10
2. PHPStorm 2.1
3. PHPStorm only runs on SUN JDK ( and not openjdk that comes default with Ubuntu 11.10 )
4. We need to install SUN JDK and then update java alternatives

Install SUN JDK with the following commands

sudo add-apt-repository ppa:ferramroberto/java
sudo apt-get update
sudo apt-get install sun-java6-jdk sun-java6-plugin

We then need to update the java alternatives using this command

sudo update-alternatives --config java

It should display choices as shown in the screenshot below ( choose the sun jdk version )

And thats it – just go to PHPStorm/bin and run the PhpStorm.sh

$("select-list-id").val();

Get the text of the selected item 

$("select-list-id :selected").text();

Get multiple selected values ( or loop through all selected values )

$("multi-select-id :selected").each(function(i, selected){
     var value = $(selected).val();
     var text = $(selected).text();
});

Empty a list 

$("select-list-id").empty();

Append Options to a list 

for(var i in options_list) {
  $("#edit-move-students-to-students").append(
     $('<option></option>').val(i).html(options_list[i])
  );
}

Note: Make a backup of the file before you do the following steps ( this will replace the formula with the actual result )

Example 1: Full formula replace

Lets say you have 3 columns in the sheet as below

Column 1: first name
Column 2: last name
Column 3: formula to concatenate first name and last name

Example data:

Column 1: John
Column 2: Doe
Column 3: =CONCATENATE(Column 1, ” “, Column 2)

Steps (keyboard):

1. Click on Column 3 ( the formula bar will display the formula instead of the actual text )
2. Press F2 ( for edit )
3. Press F9 ( for actually calculating the formula )
4. Hit “Enter”
5. The cell will now have the actual value instead of the formula

Steps (not so keyboard ):

1. Click on Column 4 ( the formula bar will display the formula instead of the actual text )
2. Press F2 ( for edit )
3. Select CONCATENATE(Column 1, ” “, Column 2)
4. Press F9 ( for actually calculating the formula )
5. Hit “Enter”
6. The cell will now have part of the formula calculated
7. Try changing the city from New York to Atlanta

To find a string in a file inside a directory ( searches all files in the directory )

grep -r ‘search-string’ path-to-directory

SELECT first_name, last_name, middle_name,
	CASE middle_name
		WHEN 'A' THEN 'Your Middle name starts with A'
		WHEN 'B' THEN 'Your Middle name starts with B'
		WHEN 'C' THEN 'Your Middle name starts with C'
		WHEN 'D' THEN 'Your Middle name starts with D'
	END AS middle_name_starts_with
FROM users;

1. As suggested this post is for setting up a PUBLIC git repository on GitHub ( and local one on Ubuntu )
2. Anyone will have access to this repo
3. Please do not put sensitive data ( like passwords etc ) in this project 
4. If you need a private repo, you can either “pay” at GitHub or host your own Git Server
5. Go to GitHub ( https://github.com/ ) and create a regular account
6. There is a very nice tutorial ( http://help.github.com/win-set-up-git/ ) on how to set up a git repo on your local machine – so i am not repeating it here
7. If you face problems with SSH keys, then you can try using DSA instead of RSA
8. In Linux dont forget to do this in case SSH to GitHub is not working cd ~/.ssh; $ ssh-add id_rsa
9. There is a post on Stack overflow ( http://stackoverflow.com/questions/922210/unable-to-git-push-master-to-github ) for SSH related problems
10. Once you install Git on your local system, you can also install a GUI like Smart Git
11. After copying all the public keys and stuff from your local system to GitHub, you can test to SSH to GitHub from your local system
12. GitHub dose not allow SSH access, but you can see if you are successful or not
13. Use the command ssh -vT git@github.com 
14. The end of the message will say something like “Hi username! You’ve successfully authenticated, but GitHub does not provide shell access.”
15. If there is a problem, then you can see the verbose log of what SSH was trying to do and refer to Step 9
16. Use the “New Repository” button in you Dashboard to create a new repo ( Lets name it “test” and put the description as “test-repo”)
17. When you finish creating a new repo, GitHub will give you some nice instructions to follow on your local machine, follow them -
    Note – i have a directory called GIT on my desktop and all my projects are located there

Global setup:
 Set up git
  git config --global user.name "Your Name"
  git config --global user.email your-email@gmail.com

Next steps:
  mkdir test
  cd test
  git init
  touch README
  git add README
  git commit -m 'first commit'
  git remote add origin git@github.com:username/test.git
  git push -u origin master

18. Basically you are creating a README file and pushing it to GitHub ( my folder structure is /home/naveen/Desktop/GIT/test )
19. After these steps you should be able to see README in your GitHub account under repo “test” with the message “First Commit”
20. Now lets add another file to “test”

touch index.php
echo "<?php echo 'Hello World';" > index.php
git add index.php
git push -u origin master

21. You should now be able to see index.php in your GitHub account
22. Lets make some changes to index.php

echo "echo 'Hello World - 1';" >> index.php
git diff

23. git diff will show you the differences

git add index.php
git commit

24. When you use git commit instead of git commit -m ‘your message’ ,  a vim editor opens up by default and you can see what all changes have been done
25. You will have to type a commit message and exit
26. Type the message “added hello world 1″ on the first line , then press escape , then press and hit enter – you will see the commit message
27. This is better way to see all files that have changed rather than just commit with a direct message
28. To change your editor from vim to nano use the command git config –global core.editor “nano”  

git push -u origin master

24. Changes should be  reflected on GitHub
25. To remove  an entire git repo, all you need to do is to delete the .git folder in your repository then you can do an init for a fresh start
26. Next how to clone an existing PUBLIC repository from Github
27. First we will delete our existing “test ” repo on our local machine, then we will clone the “test” repo on GitHub that we just created ( take care where you execute rm -rf and always keep a backup of your old git repos )

rm -rf .git
rm index.php
rm README
cd ..
rmdir test
git clone git://github.com/username/test.git

28. You will now get back the test repo on GitHub – you can make modifications and repeat the cycle if necessary
29. To add some color to your command line interface use the below commands

git config --global color.status auto
git config --global color.branch auto

30. Change remote-origin with this command ( github does not allow git protocol – you might get an error while pushing )

git remote set-url origin git@github.com:username/project_name.git

31. To show all files in a branch

git ls-tree -r branch

32. To compare the same file from 2 branches

git diff branch_1..branch_2 file.txt

Good tutorials and references at http://gitref.org

I will update the post as an when i learn more

I always used to be asked for credentials during logon – even though i saved my credentials

This error would creep up

Your system administrator does not allow the use of saved credentials to logon to the remote computer 
computername/ipadress because its identity is not fully verified. Please enter new credentials.
The logon attempt failed

There is no-trust-relationship when connecting 2 computers from different domains. Windows uses NTLM in this case and the default domain machine policy does not allow use of saved credentials.

To Do:

• On your local machine Open Windows command prompt type: gpedit.msc -> Press Enter -> a new window will popout
• Go to Local Computer Policy –> Computer Configuration –> Administrative Templates –> System –> Credentials Delegation
• Double Click on “Allow Delegating Saved Credentials with NTLM-only Server Authentication”
• By default it will be “not configured”
• You will see radio buttons -> Enable the policy
• Click the “Show” button in the options window below and enter the value “TERMSRV/*”  (without quotes) into the list.
• Click Apply button
• Do the same thing for the following policies:
        Allow Delegating Saved Credentials
        Allow Delegating Default Credentials with NTLM-only Server Authentication
        Allow Delegating Default Credentials 
• Close all windows
• Open a command prompt and use “gpupdate /force” command to apply the policy directly

1. wkhtmltopdf is one of the best html to pdf conversion tools i have come across
2. It is a command line utility
3. It is very fast and converts most html pages – impressive  css support
4. Integration with php is a breeze ( after struggling for 6 hrs )

<?php
    error_reporting(E_ALL);
    ini_set('display_errors', '1');
    $cmd = "/usr/local/bin/wkhtmltopdf http://www.yahoo.com /home/username/Desktop/yahoo.pdf";
    $t = shell_exec($cmd);
    exit();

$cmd = "/usr/local/bin/wkhtmltopdf path-to-html-file path-to-pdf-file";