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            try
                //File öffnen
                if FileExists(FileName) = true then begin
                    hFile := TFileStream.Create(FileName, fmOpenRead, fmShareDenyNone) //keine Beschränkung des Zugriffs
                    //hFile := TFileStream.Create(FileName, fmOpenRead, fmShareDenyRead) //andere Applikationen haben Schreibrecht,
                                                                                       //aber kein Leserecht
                    //hFile := TFileStream.Create(FileName, fmOpenRead, fmShareCompat)   //Sharing is compatible with the way FCBs are opened
                    end{erster if-Zweig}
                else begin
                    result := eCantOpenFile;
                end;{if}
            except
                //Fehlerbehandlung
                result := eCantOpenFile;
            end;{try..except}                    

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inherited Create(FileOpen(FileName, Mode));                    

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inherited Create(FileOpen(FileName, Mode or Rights));                    

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hFile := TFileStream.Create(FileName, fmOpenRead or fmShareDenyNone)                    

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constructor TFileStream.Create(const FileName: string; Mode: Word; Rights: Cardinal);                    

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  if Mode = fmCreate then
  begin
    inherited Create(FileCreate(AFileName, Rights));
    if FHandle = INVALID_HANDLE_VALUE then
      raise EFCreateError.CreateResFmt(@SFCreateErrorEx, [ExpandFileName(AFileName), SysErrorMessage(GetLastError)]);
  end
  else
  begin
    inherited Create(FileOpen(AFileName, Mode));
    if FHandle = INVALID_HANDLE_VALUE then
      raise EFOpenError.CreateResFmt(@SFOpenErrorEx, [ExpandFileName(AFileName), SysErrorMessage(GetLastError)]);
  end;                    

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function FileCreate(const FileName: string; Rights: Integer): Integer;
{$IFDEF MSWINDOWS}
begin
  Result := FileCreate(FileName);
end;
{$ENDIF}
{$IFDEF LINUX}
begin
  Result := Integer(open(PChar(FileName), O_RDWR or O_CREAT or O_TRUNC, Rights));
end;
{$ENDIF}                    

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function FOpen(FileName: string; Mode: LongWord): Integer;
const
  AccessMode: array[0..2] of LongWord = (
    GENERIC_READ,
    GENERIC_WRITE,
    GENERIC_READ or GENERIC_WRITE);
  ShareMode: array[0..4] of LongWord = (
    0,
    0,
    FILE_SHARE_READ,
    FILE_SHARE_WRITE,
    FILE_SHARE_READ or FILE_SHARE_WRITE);
  OpenMode: Cardinal;
begin
  Result := -1;
  if Mode and fmCreate>0 then
    OpenMode:= CREATE_ALWAYS
  else
    OpenMode:= OPEN_EXISTING;
  if ((Mode and 3) <= fmOpenReadWrite) and
    ((Mode and $F0) <= fmShareDenyNone) then
    Result := Integer(CreateFile(PChar(FileName), AccessMode[Mode and 3],
      ShareMode[(Mode and $F0) shr 4], nil, OpenMode,
      FILE_ATTRIBUTE_NORMAL, 0));
end;