one thing I'd like to clarify is that principles NEVER change however moderen you may become
As laserlight has pointed out, They do evolve. and currently languages with good concurrent support are the future languages.
You might find yourself in trouble when you find that what you've been always doing in Turbo C is no longer accepted in C standard. (eg modifying string literal).
Bad habits are hard to break.

You know after learning C++ on the same compiler
Wow on same compiler!, you know C++ evolve much since then...
Good luck with your o'd compiler.