Vim does not remember any settings. It starts afresh every time. It will read your initialization scripts (not just
~/.vimrc but ALL
~/.vim/* files) upon startup. If what you want isn't happening automatically, you'll need to do something to make it happen. I recommend using a filetype plugin.
Let's say your filetype is
taro-enc. You should write a file:
~/.vim/after/ftplugin/taro-enc.vim with your vimscript (
enc=iso-2022-jp). Now open the file and manually set the filetype
:set filetype=taro-enc. Now your single file plugin should be sourced!
Well, almost. Perhaps you need to enable this feature. Make sure this is in your vimrc:
:filetype plugin on.
And ok 1 more issue - this is manual! If you want to automatically detect your file as of
filetype=taro-enc, then you can use your ~/..vim/filetype.vim file. (Mine is linked).
You can realistically put all of this stuff just inside your vimrc, but it's better to keep organized. Makes your code more semantic.
Btw, I recommend using full names of commands when communicating with people to avoid silly issues like