i have problem if more than one client access 1 file with this method in datasnap at the same time:

i have problem if more than one client access 1 file with this method in datasnap at the same time:

function TServerMethods.DownloadJPEGFile(sFilePath: string): TJSONArray;
var
  strFileStream: TFileStream;
begin
  strFileStream := TFileStream.Create(sFilePath, fmOpenRead);
try
  Result := TDBXJSONTools.StreamToJSON(strFileStream, 0, strFileStream.Size);
finally
  strFileStream.free;
end;
end;

error message: cannot acces the file because it is being used by another prosess.

how to make this file can access more than client in the same time.