using external file explorer

http://midnight-commander.org/

Then config it to use external editor vim

For open all files in one vim, one may open a vim server

vim --servername server_name_here

then open in other location

vim --servername server_name_here --remote file_name_here

One can get all lines:

vim --servername server_name_here --remote-expr "getline(1,'$')"

One can issue commands:

vim --servername server_name_here  --remote-send "<ESC>"

Through –remote-expr and –remote-send, one could almost totally control the vim server.