GrayLib::cFileMemMap Class Reference

#include <cFileMemMap.h>

Public Member Functions
	cFileMemMap () noexcept
	~cFileMemMap ()
HRESULT	OpenView (DWORD dwDesiredAccess, STREAM_OFFSET_t nViewOffset, size_t nViewSize)
void	CloseView ()
size_t	get_ViewSize () const
HRESULT	OpenMemMap (const FILECHAR_t *pszName, DWORD dwDesiredAccess, size_t nViewSize, HANDLE hFile=INVALID_HANDLE_VALUE)
void	CloseMemMap ()
HRESULT	OpenMemMapV (const FILECHAR_t *pszName, DWORD dwDesiredAccess=FILE_MAP_ALL_ACCESS, size_t nViewSize=0, HANDLE hFile=INVALID_HANDLE_VALUE)
	UNITTEST_FRIEND (cFileMemMap)

Public Attributes
cOSHandle	m_MapFile
	similar to cFile ? More...
cMemBlock	m_View
	pointer to the memory block/window in m_MapFile. More...

Detailed Description

Memory mapped OS file that may be shared between processes.

Note

a similar effect can be achieved using a shared data segment in a DLL. (or cOSPipe or other) Multi process can see the shared memory segment in the DLL. "#pragma data_seg (".SHARED") and link /SECTION:.SHARED,RWS" like shmget() and shmat() for linux

Constructor & Destructor Documentation

cFileMemMap()

GrayLib::cFileMemMap::cFileMemMap ( )

inlinenoexcept

~cFileMemMap()

GrayLib::cFileMemMap::~cFileMemMap ( )

inline

Member Function Documentation

CloseMemMap()

void GrayLib::cFileMemMap::CloseMemMap ( )

inline

CloseView()

void GrayLib::cFileMemMap::CloseView

(

)

Close the memory view, but keep the file.

get_ViewSize()

size_t GrayLib::cFileMemMap::get_ViewSize

(

)

const

Note

_WIN32 "::GetFileSize( m_MapFile.m_h, nullptr )" doesn't work!!

OpenMemMap()

HRESULT GrayLib::cFileMemMap::OpenMemMap	(	const FILECHAR_t *	pszName,
		DWORD	dwDesiredAccess,
		size_t	nViewSize,
		HANDLE	hFile = INVALID_HANDLE_VALUE
	)

If hFile is INVALID_HANDLE_VALUE then just a memory page is used. else Take some existing hFile and create a memory mapping for it.

• pszName = The name of the file mapping object (Not the name of the file) for multi-process sharing.
• dwDesiredAccess = FILE_MAP_WRITE, FILE_MAP_READ,
  

OpenMemMapV()

HRESULT GrayLib::cFileMemMap::OpenMemMapV ( const FILECHAR_t *  pszName, DWORD  dwDesiredAccess = FILE_MAP_ALL_ACCESS, size_t  nViewSize = 0, HANDLE  hFile = INVALID_HANDLE_VALUE  )

inline

Open a memory map and a view to it as a single call.

• dwDesiredAccess = FILE_MAP_READ, FILE_MAP_WRITE

OpenView()

HRESULT GrayLib::cFileMemMap::OpenView	(	DWORD	dwDesiredAccess,
		STREAM_OFFSET_t	nViewOffset,
		size_t	nViewSize
	)

change the map view into the file opened as m_MapFile

• dwDesiredAccess = FILE_MAP_READ, FILE_MAP_WRITE ASSUMED m_MapFile != nullptr

UNITTEST_FRIEND()

GrayLib::cFileMemMap::UNITTEST_FRIEND

(

cFileMemMap

)

Member Data Documentation

m_MapFile

cOSHandle GrayLib::cFileMemMap::m_MapFile

similar to cFile ?

m_View

cMemBlock GrayLib::cFileMemMap::m_View

pointer to the memory block/window in m_MapFile.

---

The documentation for this class was generated from the following files:

• c:/Dennis/Source/Gray/GrayLib/include/FileSys/cFileMemMap.h
• c:/Dennis/Source/Gray/GrayLib/src/FileSys/cFileMemMap.cpp