WOW64_CONTEXT structure (winnt.h)

Represents a context frame on WOW64. Refer to the header file WinNT.h for the definition of this structure.

Syntax

typedef struct _WOW64_CONTEXT {
  DWORD                    ContextFlags;
  DWORD                    Dr0;
  DWORD                    Dr1;
  DWORD                    Dr2;
  DWORD                    Dr3;
  DWORD                    Dr6;
  DWORD                    Dr7;
  WOW64_FLOATING_SAVE_AREA FloatSave;
  DWORD                    SegGs;
  DWORD                    SegFs;
  DWORD                    SegEs;
  DWORD                    SegDs;
  DWORD                    Edi;
  DWORD                    Esi;
  DWORD                    Ebx;
  DWORD                    Edx;
  DWORD                    Ecx;
  DWORD                    Eax;
  DWORD                    Ebp;
  DWORD                    Eip;
  DWORD                    SegCs;
  DWORD                    EFlags;
  DWORD                    Esp;
  DWORD                    SegSs;
  BYTE                     ExtendedRegisters[WOW64_MAXIMUM_SUPPORTED_EXTENSION];
} WOW64_CONTEXT;

Members

ContextFlags

Dr0

Dr1

Dr2

Dr3

Dr6

Dr7

FloatSave

SegGs

SegFs

SegEs

SegDs

Edi

Esi

Ebx

Edx

Ecx

Eax

Ebp

Eip

SegCs

EFlags

Esp

SegSs

ExtendedRegisters[WOW64_MAXIMUM_SUPPORTED_EXTENSION]

Remarks

In the following versions of Windows, Slot 1 of Thread Local Storage (TLS) holds a pointer to a structure that contains a WOW64_CONTEXT structure starting at offset 4. This might change in later versions of Windows.

Windows Vista Windows Server 2008
Windows 7 Windows Server 2008 R2
Windows 8 Windows Server 2012
Windows 8.1 Windows Server 2012 R2

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Header winnt.h (include Windows.h)

See also

Thread Environment Block (Debugging Notes)

WOW64_FLOATING_SAVE_AREA

Wow64GetThreadContext

Wow64SetThreadContext