Priority scheduling (preemptive)

I have to simulate in C++ a priority cpu scheduler (preemptive).The problem is that the processes to be scheduled are generated "real time" ,while the scheduler is running.How can I make the 2 functions (process_generator() and cpu_scheduler() )run "parallel"?Also , some of the generated processes will have input/output demands.The io time is standard for every process (5 ticks).
If anyone has any good idea about this,or knows a good online tutorial,or has code for this algorithm,please reply as soon as possible