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Serves as a logical wrapper for the corresponding Win32 function. The Win32 implementation of VirtualProtect changes the protection on a region of committed pages in the virtual address space of the calling process.
Syntax
HRESULT VirtualProtect (  
    [in]  void*   lpAddress,  
    [in]  SIZE_T  dwSize,  
    [in]  DWORD   flNewProtect,  
    [out] DWORD*  pflOldProtect  
);  
Parameters
lpAddress
[in] A pointer to the base address of the virtual memory whose protection attributes are to be changed.
dwSize
[in] The size, in bytes, of the region of memory pages to be changed.
flNewProtect
[in] The type of memory protection to apply.
pflOldProtect
[out] A pointer to the previous memory protection value.
Return Value
| HRESULT | Description | 
|---|---|
| S_OK | VirtualProtectreturned successfully. | 
| HOST_E_CLRNOTAVAILABLE | The common language runtime (CLR) has not been loaded into a process, or the CLR is in a state in which it cannot run managed code or process the call successfully. | 
| HOST_E_TIMEOUT | The call timed out. | 
| HOST_E_NOT_OWNER | The caller does not own the lock. | 
| HOST_E_ABANDONED | An event was canceled while a blocked thread or fiber was waiting on it. | 
| E_FAIL | An unknown catastrophic failure occurred. When a method returns E_FAIL, the CLR is no longer usable within the process. Subsequent calls to hosting methods return HOST_E_CLRNOTAVAILABLE. | 
Remarks
This implementation of VirtualProtect returns an HRESULT value, while the Win32 implementation returns a non-zero value to indicate success, and a zero value to indicate failure. For more information, see the Windows Platform documentation.
Requirements
Platforms: See System Requirements.
Header: MSCorEE.h
Library: Included as a resource in MSCorEE.dll
.NET Framework Versions: Available since 2.0