why dont you just use sleep(1); ? this stops your loop for 1 sec.
Quote:
10 hours of gameplay
Are you sure? if sys_sec is a double (the engine is written in C/C++ , isnt it?)
with a range from -1.8e+308 to 1.8e+308 -> 3.6e+308(unsigned). so you can play 3.6e+308 secs
/60 -> 6.e+306 mins /60 -> 1.e+305 h if they used a long double (10Bit) you can play even a few hours more.
Or am I completely wrong? 
nipx