Kerem Erkan
The mind of the six billionth one…
Oh, Smashing Magazine, what hast thou done?
4PHP QR Code Generator page was posted on the twitter account of Smashing Magazine, and the traffic of this humble blog has risen twenty-fold! Not that I am complaining… 
The page seems to be useful to a lot of people, so I will probably add new features to it when I find spare time.
New blog theme, Mystique
48I was using the Arclite theme from designer Milenko Popovici (digitalnature), and went to his site to check for updates to the theme. I saw Mystique theme there and loved it instantly. So, I will be using it for my blog from now on. This man has real talent! 
System Administrator Appreciation Day
0July 31, 2009
by Kerem
in Uncategorized
Today is the 10th annual System Administrator Appreciation Day. It is probably known and appreciated by only the sysadmins in the world, so only we appreciate our own work (it seems a little pathetic, isn’t it? )
I am a full time System Administrator in the company I work at. I keep the connectivity of the company up. I make sure most of the spam goes to the trash instead of users’ mailboxes. When the servers go down at 03:00 am, I get up from my bed and go fix the problem. I am not only a sysadmin but I also help our developers when they cannot do something traditionally by just coding, as I know how systems work and how problems can be solved using different ways.
I am not a real developer, yet I can code more efficiently at times because I know the inner workings of my systems.
I love my work even if people do not understand what I do.
So, happy sysadmin day to all who work hard to make this “internet thingamajik” go on working as intended…
PS: You know that internet is wireless, right?
New PHP QR Code Generator Page
0Checking my blog stats, I saw that most people come to my Real Time QR Code Generator PHP Function post. So, I decided to create a decent page for QR Code generation instead of linking to a URL which accepts only base64 encoded variables. The new page is PHP QR Code Generator page, and now you can, not only create an image that redirects you to a web address, but also can call a phone number, send an sms and send an e-mail. Also you can just encode plain text into a QR Code image.
UPDATE: vCard and bookmarks creation added.
Hope it proves to be useful for some people out there.
Supporting Oracle FCF in Tomcat
24We use Tomcat with Apache HTTPD in our company. And as a database backend, we use a two node Oracle Real Application Cluster (RAC).
We were having stale connection problems when a RAC node was behaving abnormally, because the JDBC pool which was created by Tomcat was not getting any notification about it. So I started searching for a way to take advantage of Oracle’s Fast Connection Failover (FCF) mechanism. FCF is superior to Transparent Application Failover (TAF) as it is event based and supports load balancing across the RAC nodes. It is also superior to having no failover mechanism whatsoever.
FCF leverages Oracle Notification Service (ONS) to get information about database events. With the help of ONS, a JDBC pool which has FCF enabled can see if a RAC node is up or down and can act accordingly. To be able to use the method I am about to show, you will have to have a minimum Oracle RAC version of 10.2.0, because Oracle versions prior to that do not support “Remote ONS”, which is an essential part of this configuration.
Enabling tftpd on MacOS X (Snow) Leopard
1Enabling the tftp daemon in MacOS X Snow Leopard (or Leopard) is an easy task with little documentation. This is a quick reference. The manual page for tftpd in MacOS X Snow Leopard (or Leopard) recommends that tftpd is launched via launchd, so we will do it that way. First, we enter launchd% console using sudo:
sudo launchctl |
After that, we enable tftpd in launchd% console:
load -F /System/Library/LaunchDaemons/tftp.plist |
That’s it. Now you can put your tftp files into /private/tftpboot folder and start using tftpd.
When you are finished using the daemon, you can unload it by entering launchd% console and issuing the following command:
unload /System/Library/LaunchDaemons/tftp.plist |
If you use tftpd a lot, you can enable it at boot time by entering the following in launchd% console:
load -w /System/Library/LaunchDaemons/tftp.plist |
And to disable it from starting up at boot time:
unload -w /System/Library/LaunchDaemons/tftp.plist |
To all who sent mails and I did not answer
April 21, 2008
I have received a lot of mails about both PHP DRM Packager class and Check Quota plugin for SquirrelMail. For the last months, I have not been able to concentrate on anything and I could not reply your mails. I apologize for that from all of you.
For the PHP DRM Packager, while I would love to share the code with the rest of the world as open source, I am not able to do that for the time being. Sorry. I hope in the future, I will be able to do it.
For the Check Quota plugin for SquirrelMail, I will be working on the plugin. I still need some time to get fully back on, but I will, eventually.
Thanks to all who sent support mails to me in this period. It means a lot to me.
SquirrelMail Check Quota 2.2 released
August 6, 2007
by Kerem
in SquirrelMail
I have released Check Quota 2.2 today, with help from Paul Lesniewski of SquirrelMail Development Team. With this release, all Check Quota versions prior to this one and Quota Usage plugin maintained by Bill Shupp and Paul are obsoleted. The two plugins are now completely and officially merged.
The biggest change in Check Quota 2.2 is complete support of SquirrelMail 1.5.2 branch. Other changes are mostly bugfixes and optimizations, as well as new language strings. This means, translations of Check Quota 2.x will not work for Check Quota 2.2, so they are removed from the plugin.
Please send your translations to the SquirrelMail i18n team from now on. You can also send them to me, and I will forward them to the translation team.
You can download the new release from the downloads page.
New translations for Show User and IP 3.3 added
June 29, 2007
by Kerem
in SquirrelMail
This week two translations for Show User and IP 3.3 have arrived and added. They are Bahasa Melayu (ms_MY) and Norwegian (nb_NO). You can find the repacked plugin file from Downloads page. Thanks to Muhd Zamri MS and Arnt Gronas for giving their precious time to these translations.
PHP Captcha 1.0 released
Today I am releasing PHP Captcha 1.0.
The main difference of PHP Captcha from other free or paid PHP implementations is, that it is written to utilize ImageMagick functions through the wonderful MagickWand PHP API to create CAPTCHA images that are hard enough for bots to crack, while more readable by humans than the others.
Quoting Aleksey Kolupaev of OCR Research Team, to whom I am thankful for his help on PHP Captcha:
“Everything can be cracked, but this one is a hard nut.”
Output of default configuration:
Output of a custom (a little too unpractical) configuration:
PHP Captcha has a lot of configuration options including:
- Random background colors
- Random background noise
- Random text fill and stroke colors
- Random text string length
- Random font size
- Random text direction
- Random character rotation
- Random image swirling
- Random foreground noise and so on…
