overwrite file (so name remains the same) using miletus on raspberry pi

I am writing a datalogging program for Raspberry Pi using Miletus. I need to update the data into a local file every 15 minutes, but no matter what method I use, it always updates the name of the filename with (1), (2), etc. Is there a way to manually open a file and add a line, or to simply specify "overwrite" so that it doesn't create new files?
I have used application.writetofile, writing to a memo and then memo1.savetofile, creating a Miletus text string and using and whatever else I could find but no luck so far. I know how to do this in VCL and FMX with text files, but I can't figure out the equivalent procedure for Miletus.

Hi,

Maybe it will help to think about it the following way:
Any classes that don't start with TMiletus will most likely call the browser implementation. Classes/components starting wtih TMiletus are using a bridging mechanism to communicate with the OS.

TWebMemo is using a TStringList (which relies on browser implementation), so you will need to use TMiletusStringList directly instead.