We're a lot of things, but psychic is not one of them :P

I've never seen Khaled post anything about what he used to read (in regards to coding), but I don't know if someone helps here that knows him well and happens to know. Maybe you'll be lucky enough to get a reply from Krejt or Khaled himself smile - Of course, it is possible he didn't read any books!

From Khaled's FAQ:

Question: In which language is mIRC written?
Answer: mIRC is written in a mixture of C/C++, in pure win32 code, and compiled under Visual Studio .Net Pro.

You could try emailing him too - Khaled at mIRC dot com