It sounds like you're looking for information about a trainer (a program that modifies game memory to enable cheats like infinite ammo, god mode, etc.) for Call of Duty: Black Ops, specifically one associated with the name "Fling" (a well-known trainer creator on sites like Cheat Happens).
to see which features are currently supported for the Steam and Activision versions of the game. Check the official Call of Duty Support site call of duty black ops trainer fling
Download mirror (example): [Not a real link] It sounds like you're looking for information about
Essential Cheats: Provides standard options including infinite ammo, no reload, super speed, and rapid fire. and rapid fire.