How to end rep after a specific time duration???

[Khing]

I'm very new to this but i got the logic and idea of it.
I know that it is possible to set a rep to loop an n amount of times.
But i can't seam to find the code anywhere on how to end a rep loop after x number of minutes. Is it even possible?

I need help.

[Gintaras]

int t=GetTickCount
rep
,1
,if(GetTickCount-t >= 3000) break ;;3 s

[Khing]

int t=GetTickCount
rep
,1
,if(GetTickCount-t >= 3000) break ;;3 s

Thank yoy for replying!
But can you explain whats happening there?
If in every rep theres 1tick. Wouldn't it be just the same as rep x?

[Gintaras]

1 tick = 1 millisecond

[Khing]

Got it now! THX!