/etc/dpkg/dpkg.cfg

/etc/apt/apt.conf

/etc/apt/apt.conf.d

/etc/apt/sources.list

/etc/dpkg/dselect.cfg

vi starts and loads the last file used andmoves the cursor to the position where vi was when it last exited.

vi starts and requires the user to explicitly either create a new or load an existing file.

vi exits with an error message as it cannot be invoked without a file name to operate on.

vi starts in command mode and opens a new empty file.

vi starts and opens a new file which is filled with the content of the vi buffer if the buffer contains text.