GAURAV KUMAR

Monday, November 22, 2010

facemash experience "the social network"

hello people,
I have been constantly watching and listening "The Social Network" since the time I first watched it.Awesome movie.very inspirational.Well,I too thought about writing facemash after watching this.But,I did not want to end up facing punishment like mark.So, I didn't try to insult anyone.Just experiment and wanted to refresh my php and mysql concepts.


What we need is collection of some images.put it in a directory and provide its path in the code.for this example I will use "pics" as directory which has 7 images.Now write one php script to display 2 images randomly and let user click on any of this.Now,one more script to check which image was clicked and calculate the new rank of both image.I am sharing a piece of code here.

require_once("sql.php"); //sql.php connects to the database.
srand(time());
$r1 = rand()%7;
srand(time());
$r2 = rand()%7 ;
while($r1 == $r2)
{
srand(time()) ;
$r2 = rand()%7 ;
}
$query1 = "SELECT * FROM pic WHERE picid = '$r1'";
$result1 = mysql_query($query1);
$row1 = mysql_fetch_array($result1);
$query2 = "SELECT * FROM pic WHERE picid = '$r2'";
$result2 = mysql_query($query2);
$row2 = mysql_fetch_array($result2);
$pic1 = $row1['pic'] ;
$pic2 = $row2['pic'] ;

give image with its link in the html part of the code href='mash.php?id1=$r1&id2=$r2' img src=pics/".$pic1


href='mash.php?id1=$r2&id2=$r1'img src=pics/".$pic2


now when this page redirects to mash.php,new rank of both images is calculated based on the algorithm you wanna use.here, we have defined 3 variables.'h' is no. of hit on the image,'d' no. of times the image has been displayed.'rank' shows point given to image.use get method to catch variables to update database containing no. of hits of an image.
$id1 = $_GET['id1'];
$id2 = $_GET['id2'];

$query1 = "SELECT * FROM pic WHERE picid = '$id1'";
$result1 = mysql_query($query1);
$row1 = mysql_fetch_array($result1);
$query2 = "SELECT * FROM pic WHERE picid = '$id2'";
$result2 = mysql_query($query2);
$row2 = mysql_fetch_array($result2);

$h1 = $row1['h']+1;
$d1 = $row1['d']+1;
$rank1 = [algo to calculate new rank];

$h2 = $row2['h']; // no. of hit remains same for the image not clicked.
$d2 = $row2['d']+1;
$rank2 = [algo to calculate new rank] ;

$res1 = mysql_query("UPDATE pic SET h='$h1',d='$d1',rank='$rank1' WHERE picid='$id1' ") ;
$res2 = mysql_query("UPDATE pic SET h='$h2',d='$d2',rank='$rank2' WHERE picid='$id2' ") ;


So,this was my experience.Worked without any problem.See ya.

Thursday, September 2, 2010

UNSUCCESSFUL UBUNTU KERNEL UPGRADE TO 2.6.32-24


Hi all,
Just a month before 10.10 release,ubuntu 10.04 has created a problem for me.This post is more like a problem statement because I haven't figured out the solution yet.Last night I was upgrading my kernel to 2.6.32-24.After that my network manager was not running.I thought something was wrong with upgrade.So I rebooted and was shocked when I saw the grub menu.Previously, Grub menu used to show kernel versions 2.6.32-21, 2.6.32-22, 2.6.32-23 and their recovery options.Out of that 2.6.32-23 could not be used to boot.So,I used to boot through 22.But now,I could see only 23 and my system did not boot.when i tried to edit this option(generic kernel 2.6.32-23 in grub menu screen), I got first line as recordfail as shown in above image.

Then I tried to search on internet but found nothing important.Tried live cd of ubuntu 9.04 and tried to reinstall kernel.tried "sudo update-grub" and also grub-pc.Then checked /usr/src of 10.04 where I saw all previous kernel images along with 2.6.32-24.Now it looks like latest kernel couldn't be written but previous images were removed and only remained kernel is corrupt.So,I am not able to boot into ubuntu. Right now only solution is to reinstall 10.04.hoping a better solution from someone.

Sunday, May 30, 2010

Summer Internship :First week

hi all,
Right now I am at nagda(M.P.) for my internship at GRASIM chemicals.It's been a week and I am enjoying it completely.We are a group of 10 students in chemical division.Normally we go to the plant and visit different manufacturing sites.Due to strict discipline, we wear a helmet which we try to put on and off enormous times.Since I came here,1st thing I was looking for was internet connection but didn't find much options at such a place.After so much analysis, we thought to use GPRS connection.I recharged my airtel sim for unlimited plan.But now I have realized that it is in roaming, so it's slower than i had expected.

Finally we have 2 connections and 6 students in our group.So, we are always experimenting with creating shared connections.Sometimes we use LAN wire to connect.Sometimes,we create wireless ad-hoc and sometimes create proxy server(using privoxy).Till now we are having fun.Yesterday we went to ujjain to visit famous "Mahakaleshwar" temple.There we had a funny incident.When we bought the tickets for returning,the train started taking off.We entered into different class due to rush and ended up paying fine for that.Actually it wasn't fine,it was bribe.We were in no position to negotiate ,so we paid the money.We didn't get the receipt but paid less money and became the integral part of corruption.Although we had done no mistake considering the situation.
anyway that was a lesson for all of us.Now we have 50 days more to live at this place.Hope to spend it nicely.

Monday, May 3, 2010

Download speed through apt-cacher and dependency problem with downloading so many packages at a time








hi,
I am not able to stop experimenting with ubuntu lucid lynx the time I installed it.With the apt-cacher,it's easy to download all the packages that you like.So,I was there with synaptic package manager and kept on selecting large number of packages.Finally I got a collection of 148 packages with 220 MB size.When I started to download,I saw variation of speed which is very common but I would like to point it out by some snap-shots.
1st picture shows the usual speed of download through apt-cacher which is 347 KB/s.2nd one shows unusual high speed 2843 KB/s.











But sometime we suffer low speed also.Just like this.


Now,apart from speed,there is one more thing that I would like to share.Since I selected a lot of packages and started downloading all,I got some installation problem.All the packages were downloaded but couldn't be installed properly.Very less packages were installed because of dependency problem.No idea how did it happen.Probably,when there is a huge number of packages ,some of them might have dependency due to others files in the download list.So,in my view,large number of packages should not be installed at a time.

By the way, I sent these dependencies report to developers officially.Here is one screen-shot which explains it.


Conclusion :- try installing less number of packages at a time.

Saturday, May 1, 2010

performance review of ubuntu 10.04 lucid lynx

hello friends,
Ubuntu launched its Final release of lucid lynx 10.04 just 2 days before and I couldn't stop trying it as soon as I could.Reason is not that I was waiting eagerly for its final release.Real reason is that I had done some mistake in hard disk partition while installing slackware which caused me loss of linuxmint which I was using for a very long time.So, finally I thought to try fresh and final release of 10.04.
oh boy,What an OS.Surprisingly it can be called as the perfect OS.Lookwise,it has got better.Also,the most exciting feature is its boot time.Amazing boot time must have impressed everyone.Shutdown time is also faster.This has got attention of some people who are claiming that skipping disk check can also reduce boot time.Anyway,I don't want to create any controversy here.
Talking about look,It gives a sight of mac.The minimize, maximize and close buttons of window is on the left side which gives you feeling of working on mac.Anyway that feature was available previously also but not as default(a package "mac4lin" changes the look in that manner).New Gwibber social client is also very exciting.Gwibber can be configured to broadcast status on facebook,twitter etc. and to see other's status.
Recently "ubuntu tweak" became my latest crush as It has got nice and sexy packages which synaptic package manager didn't let me try directly.visit ubuntu-tweak.com for more info about tweak.As I am in a university which does not provide with a superfast internet connection but allows downloading packages with apt-cacher,I couldn't stop downloading all the packages which caught my attention.Well,It's definitely wastage of resource.
In final words,ubuntu 10.04 is just lovable and awesome and great experience so far.Don't know how soon the bugs will come out.Till then,enjoy lucid lynx.Happy open source.

Saturday, April 10, 2010

GPG public key

Hi,
As I was searching why my gpg public key is not working,I suddenly found answer.Actually gpg public key contains some extra words also which I neglected.public key can be viewed in terminal by typing :

gpg --armor --export [your public key id]

Now complete output is the public gpg key including "-----BEGIN PGP PUBLIC KEY BLOCK-----" and "-----END PGP PUBLIC KEY BLOCK-----".Initially I was taking only middle part.One more thing public key requires public key id which can be viewed by typing "gpg --list-keys". The pub part shows id.This command displays whole list of keys.So, if someone has made more than one key pairs,then it is useful to see which public key is for which public key id.As I successfully generated my public key, I am going to share it. It is right below :-

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.4.9 (GNU/Linux)
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=+Uo3

-----END PGP PUBLIC KEY BLOCK-----



And Now I am working on sending a mail with encryption by my private key.Hope,It works.

Thursday, April 8, 2010

GPG encryption

recently I came to know about GPG encryption.It means Gnu Privacy Guard.GPG is a command line tool with features for easy integration with other applications also.GPG is mostly used for secure communication and storing data in encrypted form.There are other uses also which I am not discussing right now.

Actually when I was filling a form for account in a site,I was asked for pgp/gpg public key and then I started wandering around to search for it.It is open source and mostly used in command line which I like.There is a windows version of it also.There are so many online pages with uncountable words for its description that I got confused sometime.But finally I figured out the theory behind it.It is like this.

There are 2 type of keys generated by gpg.One is public and another is private.Public keys can be distributed to your friends and published anywhere.With public gpg keys someone can encrypt the message and send it to you.Now, to decrypt it we need the private key which is only with you.So this way emails can be securely sent.Even if somebody sniffs the mail in the middle,It will be secure because the attacker will not have the private key to decrypt it.To create your own key pair just type gpg --gen-key in command line and follow rest instruction(You will mostly choose default values).This way you can export your public keys.But unfortunately my public keys are not working for no reason.I am still looking for answer.


But I did use gpg encryption to my file which is very easy to use and fun to watch.I am going to show what exactly I did.In the terminal just make a simple file. e.g

$ echo "my first encryption" >gen hit enter

$ gpg -e gen it will ask for user ID,use your own user ID

And done! Now hit terminal with ls command and see that there is another file named gen.gpg which is encrypted.Now If you deleted old file named gen then the content can only be viewed by opening gen.gpg which needs password.To decrypt it,put gpg -d gen.gpg in command line and hit enter.Now it will ask for the passphrase which is confidential and it makes the file secure.

Saturday, March 27, 2010

external hard disk drive

hello there,
I recently bought an external hard disk drive of 1TB. great experience till now.It is of 3.5" and so definitely not portable and also requires external power supply.I just roamed around every shop at nehru place(great place for electronics goods in India).Finally I compared brand value and prices of mainly 3-4 companies like WD,seagate,Iomega etc.Finally WD was my choice.same product was available in 2 different packages.One with external power supply and another with USB power supply.price for USB power supply was almost double.so I preferred to take the one with external power supply.With this I got 2 years of on site warranty which I do not think I will need.Today is saturday and customer care center is open from monday to friday only.So I will have to register my product on monday in order to get warranty of 2 years and free telephone service of 30 days.

At last,great product to use and one more thing.you do not get 1024 GB by buying 1TB hard drive. you get only 930 GB if you calculate. Multiply (1000/1024)^4 with 1024.

Wednesday, January 20, 2010

SEARCH ENGINE

hi friends,
what comes to your mind when you want to surf a website and you don't know its address?Without even thinking your answer would be google . Google is so common that most people keep it as homepage.Imagine google server crashes and you need to search something important immediately.


just to be safe,we should know about other search engines also.every search engines use different algorithm.Sometimes it's fun to search same keywords in different search engines and see what is the difference in result.so, there are many reasons to try different search engines.I have tried this many times.so, I am providing here the links in case you want to try.

guruji

ask

bing

altavista

lycos


this is all for now...
bye..