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Launch Control, antilag, and rev limiters

rev limiters, launch control, and antilag, are all different things.
Antilag is typically accomplished via combustion continuing into the exhaust manifold to spin the turbocharger, but without accelerating the engine. This can be at light part throttle or zero throttle by the driver, but the system will hang the throttle open slightly (or slightly more than standard target) and allow more mass flow through the turbo. it will also add more fuel and greatly delay ignition. The result is a lot of really hot exhaust gasses to spin the turbocharger. You usually do as little of this as possible, as this will melt almost any turbo charger and manifold. Usual best implementation is closed loop on turbine speed (and on a car with lots of cam control and DBW). Just enough energy to hold turbine speed target is the goal, as more will be excess heat/energy dumped into the components.
Launch control is a system to aid the driver in getting off the line more efficiently. This generally means minimizing wheelspin. This can be used in cases where traction control is illegal or otherwise unavailable, as most sanctioning bodies will let you ride preset torque or speed/acceleration targets as long as the system is not closed loop.
Rev limiters are a method of preventing overspeeding of the engine under its own power. This can be accomplished by cutting air, cutting fuel, or cutting ignition.