I am not sure of the exact behaviour of Notepad here. While I don't know how to make vim do that based on some existing text in a file, I could make vim do something similar for files of a certain extension, by adding this to ~/.vimrc:

au BufWritePre *.log :normal G"=strftime("

%b %d, %Y %X

")^Mp

Explanation:

• au - stands for AutoCommand, the vim way of executing some action for some event.


• BufWritePre - the vim event for just before writing out a file.


• *.log - the files to do this for (you could pick another extension)


• :normal - Go to normal mode (the mode you're usually in when you start vim)


• G - go to the last line


• "=strftime("
%b %d, %Y %X
")^M - Into the default buffer ("), copy the output of the strftime function (the ^M is a literal newline, obtained by pressing CtrlV, then Enter)


• p - then paste the buffer.

Each time I write the file using :w, the current date will be appended to the file:

$ vim test.log

$ vim test.log

$ cat test.log 

I did some work.



Oct 26, 2014 01:15:55  IST



Didn't I?



Oct 26, 2014 01:16:02  IST

This is quite customizable. You can pick your file extension, leave out the G if you want to append the date after the current line, modify the time format, use other events (see :h autocmd-events).