Nobody/Anonymous - 2007-04-25

A question related to this issue: does anyone know a good, free utility to convert character encoding for files in batch?

I want to change character encoding for a number of files. I start with one.
I open the file with UCS-2 Little Endian encoding and switch to Format, ANSI.
This is seen as a change, since the disk icon on the tab turns red.
But there seems no way to undo this change.
Also, when I change back to UCS-2 Little Endian encoding manually, the icon remains red.

Now, I can tell there wasn't really _any_ change in the text itself, because I can't undo anything. But how can I tell if the file is still or is not the same anymore as when I opened it?

How do I know what the original file encoding was? Should I really remember that when I change to ANSI?