Debug Hook Function Writing

This topic applies to:

Edition	Visual Basic	C#	C++	Web Developer
Express			Native only
Standard			Native only
Pro and Team			Native only

Table legend:

	Applies
	Does not apply
	Command or commands hidden by default.

This section describes a number of custom debug hook functions you can write that allow you to insert your code into some predefined points inside the debugger's normal processing.

In This Section

• Client Block Hook Functions
  Provides guidance and a prototype for writing functions that validate or report the contents of the data stored in _CLIENT_BLOCK blocks.

• Allocation Hook Functions
  Defines an allocation hook function, explores its different uses, points out restrictions, and provides a prototype.

• Allocation Hooks and CRT Memory Allocations
  Describes the restriction on allocation hook functions of explicitly ignoring _CRT_BLOCK blocks if they make any calls to C run-time library functions that allocate internal memory. This topic also lists the consequences if your allocation hook does not ignore _CRT_BLOCK blocks (with examples) and how to change the default allocation hook function, CrtDefaultAllocHook.

• Report Hook Functions
  Discusses _CrtSetReportHook, which you can use to filter reports to focus on specific types of allocations. This topic also provides a prototype.

Related Sections

• CRT Debugging Techniques
  Links to debugging techniques for the C Run-Time Library, including using the CRT Debug Library, macros for reporting, differences between malloc and _malloc_dbg, writing debug hook functions, and the CRT debug heap.