SymRegisterFunctionEntryCallback64 Function

Debug Help Library

SymRegisterFunctionEntryCallback64 Function

Registers a callback function for use by the stack walking procedure on Alpha computers.

This function supersedes the SymRegisterFunctionEntryCallback function. For more information, see Updated Platform Support.

BOOL WINAPI SymRegisterFunctionEntryCallback64(
  __in          HANDLE hProcess,
  __in          PSYMBOL_FUNCENTRY_CALLBACK64 CallbackFunction,
  __in          ULONG64 UserContext



A handle to the process that was originally passed to the StackWalk64 function.


A SymRegisterFunctionEntryCallbackProc64 callback function.


A user-defined value or NULL. This value is simply passed to the callback function. Normally, this parameter is used by an application to pass a pointer to a data structure that lets the callback function establish some context.

Return Value

If the function succeeds, the return value is TRUE.

If the function fails, the return value is FALSE. To retrieve extended error information, call GetLastError.


The SymRegisterFunctionEntryCallback64 function lets an application register a callback function for use by the stack walking procedure. The stack walking procedure calls the registered callback function when it is unable to locate a function table entry for an address. In most cases, the stack walking procedure locates the function table entries in the function table of the image containing the address. However, in situations where the function table entries are not in the image, this callback allows the debugger to provide the function table entry from another source. For example, run-time generated code on Alpha computers can define dynamic function tables to support exception handling and stack tracing.

All DbgHelp functions, such as this one, are single threaded. Therefore, calls from more than one thread to this function will likely result in unexpected behavior or memory corruption. To avoid this, you must synchronize all concurrent calls from more than one thread to this function.



Requires DbgHelp.dll 5.1 or later.


Declared in Dbghelp.h.


Use Dbghelp.lib.


Requires Dbghelp.dll.

See Also

DbgHelp FunctionsSymRegisterFunctionEntryCallbackProc64

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Build date: 9/25/2007

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