Doing this project could seriously damage your system. If you implement this project, anyone, and I mean anyone , on the planet with Internet access and an e-mail account has the potential to execute any command, even as root, on your system. Please don't attempt this project if you are not 100% sure you can secure your system from unauthorized use. In plain English: Don't do this project unless you know what you are doing, and don't blame me if you screw it up and get your system hacked. I warn you.
You know what? Just don't do it. Just read the chapter and learn. But don't do it. You know what? Don't even read this chapter. Just skip right past it and go on to the next chapter. Okay, now I'm thinking you just shouldn't read the book at all. In fact, just return the book from wherever you bought it, just to be on the safe side. I mean, you can't be too sure this code won't jump from the book and into your computer and cause irreparable damage. If you can't return it, burn it. Do whatever it takes, but don't do this project.
Okay, do it if you want to, but don't say I didn't warn you about the risks. This is seriously risky stuff I'm talking about. Think about this when you try to log in one day and your hard disk has been wiped clean by some hacker who discovered he can send a simple e-mail containing a few simple commands to your system. You have been warned . Do this project at your own risk. Now, if you're still reading this chapter carry on!