Detecting the last empty line in a file

[Ti_Thom]

Hi,
i am writing a piece of code where i modify a file (add and remove entire lines).
The problem is that i am unable to grab the last empty line. The current code is :

QStringList file_text;
while (!in.atEnd()) {
  QString line = in.readLine();
  file_text.push_back(line);
}
file.close();
//processing the lines and then save

QStringList file_text;
while (!in.atEnd()) {
  QString line = in.readLine();
  file_text.push_back(line);
}
file.close();
//processing the lines and then save

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is there any way to get the last empty line ? (or at least to detect if there is one)