macro question

[david sowerby]

Hi, in Vim/Neovim I can save a copy of the file when I exit. The copy is 
renamed file-$(date +%s).bak. This gives me a file with an increasing number 
plus .bak. It looks like "date+%s" and  "&stime" do the same thing. Is this 
possible in vile? I know I can save a file as file.bak but I like to save a 
series of changed files, not just one. 
So a macro that saves a copy and I then call that macro with write-hook.  
Thanks.
  

==========================================
Politics is like driving a car: If you want to go forward you put it in D,
if you want to go backwards you put it in R.