date time subtraction

[perinho]

I want to create a batch file that will read a string of numbers (e.g. 20180517120101) from inside a text file (e.g. C:\Users\Public\Documents\Admin\exetime.txt) and recognize these as date and time (yyyyMMddHHmmss)
the batch file will then subtract the current time from this, and write the answer into another text file (e.g. C:\Users\Public\Documents\Admin\elapsed.txt)
The answer would preferably be in days (e.g. 0.2 or 64)

I have a low level knowledge of coding and wondering is this even possible?
If this is possible, a solution would be fantastic.

Many thanks.
p.

[Squashman]

I would use Dave's JTimeStamp script to calculate the date and time offset.

[miskox]

Maybe this is useful:

viewtopic.php?p=40009#p40009

Saso