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CAtlFileMappingBase::CAtlFileMappingBase

The constructor.

CAtlFileMappingBase( 
   CAtlFileMappingBase& orig  
); 
CAtlFileMappingBase( ) throw( );

Parameters

  • orig
    The original file-mapping object to copy to create the new object.

Remarks

Creates a new file-mapping object, optionally using an existing object. It is still necessary to call CAtlFileMappingBase::MapFile to open or create the file-mapping object for a particular file.

Example

int OpenMyFileMap()
{
   // Create the file-mapping object.
   CAtlFileMappingBase myFileMap;

   // Create a file.
   CAtlFile myFile;
   myFile.Create(_T("myMapTestFile"),
      GENERIC_READ|GENERIC_WRITE|STANDARD_RIGHTS_ALL,
      FILE_SHARE_READ|FILE_SHARE_WRITE,
      OPEN_ALWAYS);

   // The file handle.
   HANDLE hFile = (HANDLE)myFile;

   // Test the file has opened successfully.
   ATLASSERT(hFile != INVALID_HANDLE_VALUE);

   // Open the file for file-mapping. 
   // Must give a size as the file is zero by default. 
   if (myFileMap.MapFile(hFile,
      1024,
      0,
      PAGE_READWRITE,
      FILE_MAP_READ) != S_OK)
   {
      CloseHandle(hFile);
      return 0;
   }

   // Confirm the size of the mapping file.
   ATLASSERT(myFileMap.GetMappingSize() == 1024);

   // Now the file-mapping object is open, a second 
   // process could access the filemap object to exchange 
   // data. 

   return 0;
}

Requirements

Header: atlfile.h

See Also

Reference

CAtlFileMappingBase Class