Thursday, June 21, 2012

Android Üzerinde C/C++ Kullanımı

Geçenlerde Ankara GTUG önderliğinde ODTÜ'de gerçekleştirilen Android Geliştiric Günleri etkinliğine katıldım ve orada bir sunum yaptım. Sunum Android üzerinde C/C++ ile yazılım geliştirmeye yönelikti. Amaç Android NDK'ya (Native Development Kit) geliştiricilerin kısa bir aşınalık kazanmalarıydı.

Bildiri dökümanına ve sunuma şu adresten ulaşabilirsiniz: http://t.co/LFqLqWHh

Aynı zamanda sunumun videosunu da izleyebilirsiniz (ses az duyuluyor maalesef).

Friday, January 6, 2012

How To Uninstall VirtualBox Guest Additions On Ubuntu

I was migrating my VMs from VirtualBox to VMware, and I needed to uninstall VirtualBox Guest Additions from a Ubuntu guest.

The system path did not have a VirtualBox uninstall tool, but a short search on Google showed the following:
/opt/<VirtualBoxGuestAdditionsFolder>/uninstall.sh

Protect Your Private Data

I was asking myself, "What will happen if my laptop is stolen?". I usually store private data both on my work and home laptops. So I was in the market for a solution to protect my private data.

I know that most operating systems have the ability to encrypt entire drives, but what I wanted was a cross platform solution, which would allow me to access the same data from different computers with different operating systems. I would also like to easily backup my encrypted data, either on an external drive or a cloud environment.

TrueCrypt, an open source and free project, gives me all the features that I want. I was really surprised at how mature the product is. I have successfully and easily used it on my Windows 7 work laptop, Ubuntu 11.10 home laptop and Mac Os X desktop at home. There's not yet a mobile version (Android, IOS etc), but it sure would be a welcome product.

Main Features as described on the TrueCrypt official website:
  • Creates a virtual encrypted disk within a file and mounts it as a real disk.
  • Encrypts an entire partition or storage device such as USB flash drive or hard drive.
  • Encrypts a partition or drive where Windows is installed (pre-boot authentication).
  • Encryption is automatic, real-time (on-the-fly) and transparent.
  • Parallelization and pipelining allow data to be read and written as fast as if the drive was not encrypted.
  • Encryption can be hardware-accelerated on modern processors.
  • Provides plausible deniability, in case an adversary forces you to reveal the password:
  • Hidden volume (steganography) and hidden operating system.
It's website is http://www.truecrypt.org/. Don't be fooled with the not so professional website. The tool itself is fantastic and easily accomplishes the task.

Wednesday, December 28, 2011

How Can you Disable a Ubuntu Service From Running at Boot?

I had an Ubuntu 11.10 VirtualBox instance which I needed to access just by SSH, so I investigated how to easily disable lightdm (the service that starts up X, the graphical user interface) from running at boot.


Seems like it's pretty easy do disable an upstart service in Ubuntu. Just create an override file and lightdm won't start at boot:
sudo echo "manual" >> /etc/init/lightdm.override
To start lightdm when you need it:
sudo start lightdm
To restore your system so that lightdm is always started on boot:
sudo rm /etc/init/lightdm.override