Are you already opening the file?
Are you already saving it?
Are you already controlling the Ctrl+S keystroke?
If those answers are all positive then you need to put the code that handles all them in functions and then call those functions just after saving.
Take a look at this
link[
^] (old Q&A that asked more or less the same). See Henry Minute's answer.
If you have problems opening and saving files then I would suggest you google, but before starting to open and close files, you can always start by handling your menus and shortcuts; put a messagebox inside your handlers to see it works...
Then start with files.
With your question I've not been able to answer nothing more precise... I hope this answer will help you.
PS: I've guessed you are having problems with Ctl+s as you specify it in the subject of your question.
Good luck.
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