Here is a web page called 'pine & vim': http//www.stripey.com/vim/pine.html
The following is excepted from that web-site:
Calling Vim from Pine
By default Pine uses its own built-in editor, Pico. To have it use Vim instead requires this setting:
That much is fairly obvious. Rather less so is that these two settings are needed as well:
These settings can be found by pressing S then C at the main menu, then using the W command to search for the string editor.
Once set up headers will be edited in Pine exactly as before, but moving ‘down’ past the last header and into the message body will cause Vim to be launched to edit the body; no headers will be loaded into Vim.
Plain Text (Human Language) Files
Different formatting settings are designed for plain text files, those just containing ordinary English (or whatever) language. There isn’t a default filetype for these, so define that all files with the extension .txt should be assumed to be ‘human’ format. Mail and news articles also fall into this category; they already have a filetype, though I also want anything in my postponed directory to be considered a news article, so I have:
autocmd BufNewFile,BufRead */.Postponed/* set filetype=mail
autocmd BufNewFile,BufRead *.txt set filetype=human
(This clobbers the help filetype, but this doesn’t seem to prevent help from working properly.)
Then Vim can be set up so that line breaks are automatically inserted in all human text. I have these at 72 characters so that even if my mail or news article is quoted by somebody else, it still fits into an 80-column terminal:
autocmd FileType mail,human set formatoptions+=t textwidth=72