Programming hook (hooking), also referred to as "hooks" is computer programming terms, refers to intercepting software module function calls between, message passing , the event delivery to extend or modify the behavior of the operating system, application, or other software components Various technologies. The code that handles intercepted function calls, events, and messages is called a hook .
Hook programming has many uses, such as debugging and extending functions. For example, intercept keyboard or mouse events before they reach the application; intercept the operating system calls of the application or other modules to monitor behavior and modify functions. It is also widely used in benchmarking programs, such as measuring the frame rate of 3D games .
Hook programming is also used for malicious code. For example, rootkits are various tools and techniques that hide the visibility of their own processes by pretending to be the output of system API calls; game plug-ins are another type of example.
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