detach thread in c?

Hi i just converted a console app to a function, the code has a statement
freeconsole() and after that the function does not work. If I take
freeconsole out then i dont get out of the loop. Is there a way to launch
the procedure in a separete console. so i can keep using my console. or put
it in another thread. I am looking around now and the only thing that i can
think of is CreateProcess, the function looks like this int
oldmain(parametes);
how can i launch it in a separete thread or console. thanks..

when i use
handle = (HANDLE) _beginthread(myfuction(),0,NULL(;
and
WaitForSingleObject(handle,INFINITE);

i dont get past begin thread and my program halts after that line