How To Fix BeEf Framework on Backtrack 5 R3

If you use Backtrack 5 r3, maybe you will find some trouble in Beef Framework when you run it. It won't work by default because it requires some works. The ruby gems need to be properly installed before before you can install and run this framework.

To install the ruby gems required, try this statements on the command line:
First, you must go to the beef directory
- cd /pentest/web/beef
- gem install --user-install bundler
- bundle install

When it's finished,
Just Open the beef installer that located in menu Backtrack -> Exploitation Tools -> Social Engineering Tools -> Beef XSS Framework -> Beef Installer
Then Just wait the process.
If the process has finished, try to open Beef again and it should be run normally.

Source: http://redmine.backtrack-linux.org:8080/issues/796
Note : So sorry if my English not good ^^

BC ( Basic Calculator)

BC is an arbitrary precision calculator language" with syntax similar to the C programming language. bc is typically used as either a mathematical scripting language or as an interactive mathematical shell. A typical interactive usage is typing the command bc on a Unix command prompt and entering a mathematical expression, such as (1 + 3) * 2, whereupon 8 will be output. While bc can work with arbitrary precision, it actually defaults to zero digits after the decimal point - so the expression 2/3 yields 0. This can surprise new bc users unaware of this fact. The "-l" option to bc sets the default scale (digits after the decimal point) to 20, and adds several additional mathematical functions to the language.