......
FileStream bob = tmpFile;
LogThis($"{tmpFile.Position} -- {bob.Position}");
Decompress(ref bob);
LogThis($"{tmpFile.Position} -- {bob.Position}");
bob.Close();
bob.Dispose();
......

private void Decompress(ref FileStream dwnFile)
{
   LogThis($"{dwnFile.Position}");
   dwnFile.Position = 50;
   LogThis($"{dwnFile.Position}");
   LogThis("DUMMY DECOMPRESS FUNCIOTN");
}

[29/11/2020 22:41:32] LOG > 51518 -- 51518
[29/11/2020 22:41:32] LOG > 51518
[29/11/2020 22:41:32] LOG > 50
[29/11/2020 22:41:32] LOG > DUMMY DECOMPRESS FUNCIOTN
[29/11/2020 22:41:32] LOG > 50 -- 50

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