Интересно узнать каким образом скрывают файлы и папки?

const
  BufSize=1024;
 
function HideFile(FileName:string):boolean;
var
  FileStream:TFileStream;
  MemStream:TMemoryStream;
  Buf: array [0..BufSize-1] of byte;
  tmp:Integer;
begin
  Result:=false;
  if not FileExists(FileName) then
    Exit;
  try
    FileStream:=TFileStream.Create(FileName,fmOpenRead);
    MemStream:=TMemoryStream.Create;
    while FileStream.Position<FileStream.Size do
      begin
        tmp:=FileStream.Read(Buf,BufSize);
        MemStream.Write(Buf,tmp);
      end;
    FreeAndNil(FileStream);
    TFileStream.Create(FileName,fmCreate).Free;
    FileStream:=TFileStream.Create(FileName+':hide',fmCreate);
    MemStream.Seek(0,soBeginning);
    while MemStream.Position<MemStream.Size do
      begin
        tmp:=MemStream.Read(Buf,BufSize);
        FileStream.Write(Buf,tmp);
      end;
    FreeAndNil(MemStream);
    FreeAndNil(FileStream);
    Result:=true
  except
    if Assigned(FileStream) then
      FreeAndNil(FileStream);
    if Assigned(MemStream) then
      FreeAndNil(MemStream)
  end
end;
 
function UnHideFile(FileName:string):boolean;
var
  FileStream:TFileStream;
  MemStream:TMemoryStream;
  Buf: array [0..BufSize-1] of byte;
  tmp:Integer;
begin
  Result:=false;
  if not FileExists(FileName) then
    Exit;
  try
    FileStream:=TFileStream.Create(FileName+':hide',fmOpenRead);
    MemStream:=TMemoryStream.Create;
    while FileStream.Position<FileStream.Size do
      begin
        tmp:=FileStream.Read(Buf,BufSize);
        MemStream.Write(Buf,tmp);
      end;
    FreeAndNil(FileStream);
    FileStream:=TFileStream.Create(FileName,fmCreate);
    MemStream.Seek(0,soBeginning);
    while MemStream.Position<MemStream.Size do
      begin
        tmp:=MemStream.Read(Buf,BufSize);
        FileStream.Write(Buf,tmp);
      end;
    FreeAndNil(MemStream);
    FreeAndNil(FileStream);
    Result:=true
  except
    if Assigned(FileStream) then
      FreeAndNil(FileStream);
    if Assigned(MemStream) then
      FreeAndNil(MemStream)
  end
end;