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CAtlFile::Read

Call this method to read data from a file starting at the position indicated by the file pointer.

HRESULT Read( 
   LPVOID pBuffer, 
   DWORD nBufSize 
) throw( ); 
HRESULT Read( 
   LPVOID pBuffer, 
   DWORD nBufSize, 
   DWORD& nBytesRead  
) throw( ); 
HRESULT Read( 
   LPVOID pBuffer, 
   DWORD nBufSize, 
   LPOVERLAPPED pOverlapped 
) throw( ); 
HRESULT Read( 
   LPVOID pBuffer, 
   DWORD nBufSize, 
   LPOVERLAPPED pOverlapped, 
   LPOVERLAPPED_COMPLETION_ROUTINE pfnCompletionRoutine 
) throw( );

Parameters

  • pBuffer
    Pointer to the buffer that will receive the data read from the file.

  • nBufSize
    The buffer size in bytes.

  • nBytesRead
    The number of bytes read.

  • pOverlapped
    The overlapped structure. See lpOverlapped in ReadFile in the Windows SDK.

  • pfnCompletionRoutine
    The completion routine. See lpCompletionRoutine in ReadFileEx in the Windows SDK.

Return Value

Returns S_OK on success, or an error HRESULT on failure.

Remarks

The first three forms call ReadFile, the last ReadFileEx to read data from the file. Use CAtlFile::Seek to move the file pointer.

Requirements

Header: atlfile.h

See Also

Reference

CAtlFile Class

CAtlFile::Write