close the group (killing all fibers).
It is legal for the calling thread to be part of the group. If waitForExit is true, it will be killed only once the function is done waiting for the other fibers to exit.
Whether the function waits for all fibers to exit before returning.
Notes: If waitForExit is false, the group cannot be reused before all fibers have actually exited.
See Implementation
close the group (killing all fibers).
It is legal for the calling thread to be part of the group. If waitForExit is true, it will be killed only once the function is done waiting for the other fibers to exit.