We can get the startup time? not the elapsed time Because if we know the time that the computer startup, we can compare this to know if the clock was adjusted. For examples:
A = Real time -> time()
B = elapsed time -> GetTickCount()
C = Teorical startup time

A = 1:45pm
B = 10 minutes
C = 1:35pm

C = A - B
but we can't probe this because we don't know the real startup time. But if

D = Real startup time
D = 12:00pm
We can compute if C = D
if C = D the clock is correct
if C <> D the clock was adjusted

C = 1:35pm
D = 12:00pm

C <> D so the clock was adjusted

BUT WE CAN TO KNOW THE STARTUP TIME???