Hitting arrow keys adds characters in vi editor

If you don't already have a .vimrc file in your home directory, create one using this:

vim ~/.vimrc

Add this line to the top of the file:

set nocompatible

Save the file and this should fix the problem for you. :)

Installing the vim package will fix the problem:

sudo apt-get install vim

There are many good vim/vi tutorials on YouTube, or the web generally. For your problem, see the article 8 Essential Vim Editor Navigation Fundamentals.

Then continue to open files as usual:

vi desired-file

With vi, when pressing i you activate the command to Insert text.
This command allows you to insert text in your file.
And right, when:

• pressing ↑ it will insert a "A",
  
• pressing ↓ it will insert a "B",
  
• ...
  

Till you deactivate this command.
To deactivate a command in vi: just press Esc
And then you will get back normal use of your arrow keys:

• ↑ to go up,
• ↓ to go down,
• ...

FYI, here are some vi commands:
_{From this source.}

:xReturn quit vi, writing out modified file to file named in original invocation
:wqReturn quit vi, writing out modified file to file named in original invocation
:qReturn quit (or exit) vi
:q!Return quit vi even though latest changes have not been saved for this vi call

↓ move cursor down one line
↓ move cursor up one line
← move cursor left one character
→ move cursor right one character

u undo whatever you just did; a simple toggle
. redo whatever you just did

i insert text before cursor, until Esc hit
I insert text at beginning of current line, until Esc hit
a append text after cursor, until Esc hit
A append text to end of current line, until Esc hit
o open and put text in a new line below current line, until Esc hit
O open and put text in a new line above current line, until Esc hit

r replace single character under cursor (no Esc needed)
cw change the current word with new text,starting with the character under cursor, until Esc hit
x delete single character under cursor
Nx delete N characters, starting with character under cursor
dw delete the single word beginning with character under cursor
C change (replace) the characters in the current line, until Esc hit
D delete the remainder of the line, starting with current cursor position

dd delete entire current line
Ndd delete N lines, beginning with the current line; e.g., 5dd deletes 5 lines
yy copy (yank, cut) the current line into the buffer
Nyy copy (yank, cut) the next N lines, including the current line, into the buffer
p paste the line(s) in the buffer into the text after the current line

0 (zero) move cursor to start of current line (the one with the cursor)
$ move cursor to end of current line
w move cursor to beginning of next word
b move cursor back to beginning of preceding word
:0Return or 1G move cursor to first line in file
:nReturn or nG move cursor to line n
:$Return or G move cursor to last line in file

/string search forward for occurrence of string in text
?string search backward for occurrence of string in text
n move to next occurrence of search string
N move to next occurrence of search string in opposite direction

To disable printing letters on pressing arrows in edit mode you can do following

vi $HOME/.exrc 

(create file if it does not exist) and then add line set nocompatible to it and save.

There are three modes in vi editor namely:

• command mode
• input mode
• default mode.

When youu open a file, you are in default mode. Now if you want to go to a specific position in your text, just use arrow keys or use h, j, k, l keys. Note that this would work only when you have not pressed i (or any other input mode entering command like a, A, I).

The reason for 'B' may be because the arrow keys in input mode don't function as arrow keys, so just press Esc to go into default mode any time. When to shift to input mode press i or a, and to navigate just press i key and use arrow keys or h, j, k, l.

I had the exact same Problem but not only on my local machine but also on connections via putty on a sles machine in a Win7 VM over a citrix receiver. Both the local host and the remote hosts show after a reinstall of Ubuntu had the exact same problem.

After finding out that

$ localectl list-keymaps 
Couldn't find any console keymaps.

Causes this strange VI behaviour I installed the package console-data which solves the issue!

sudo apt-get install console-data

Here is an explanation:

Vi is an editor that's been around a long while, with roots back to the Unix systems. It's a good tool but it has been iterated on and now there is better. Vim was written later and is that iteration. People commonly refer to vi as 'vim-minimal' and to vim is an "improved" version of vi. You can think of it like this: vi is the core and vim expands on it.

Likely how you discovered the behavior:

In order for you to have discovered this problem, you pressed "i" to enter into insert mode and then used your arrow keys to navigate the correct line and edit point. This is what caused your unexpected char issue.

Solution 1 or 2

1. vi someFile While using vi, first move to the edit point, then enter into insert mode.

2. vim someFile Simply use vim from the start.

I cannot stress enough to read the manual (man pages) or to use -h for help. Once you adjust to the patterns in the shell, man pages become your best friend. Example: man vi or man vim

Validate that Vim is installed.

Open a console window and execute:

dpkg --list | grep vim

If you get something similar to this, then you can just start using vim.

~ $ dpkg --list | grep vim
ii  vim         2:7.4.052-1ubuntu3  amd64  Vi IMproved - enhanced vi editor
ii  vim-common  2:7.4.052-1ubuntu3  amd64  Vi IMproved - Common files
ii  vim-runtime 2:7.4.052-1ubuntu3  all    Vi IMproved - Runtime files
ii  vim-tiny    2:7.4.052-1ubuntu3  amd64  Vi IMproved - enhanced vi editor - compact version

If the command prompt returns with nothing, then vim is is not installed. Use the below examples to update your repositories and then install vim.

sudo apt-get update
sudo apt-get install vim

On the off chance that you use vi or vim only when searching on the internet how to fix something and you happen to forget to type vim, there is one way that you can fix it for the future. I caution you to pay attention. You can use an alias to overwrite vi with a reference to vim so that no matter what you type in the infrequent future, you get vim without that "oops!" moment. You can always delete an alias later.

Type vim .bashrc. Move down to the empty line with only a ~ (or to any other line that starts with alias (so they're grouped together) and then press the i key to enter -insert- mode. On its own separate line, enter the following:

alias vi='vim'

Press Esc and then type :wq. Now you need to reload the file. Type source .bashrc Any other shell that opens after you have made these edits will automatically load the .bashrc file.

This can also be due to the TERM variable; set it for example like this:

export TERM=xterm

All the explanations given are a bit bizarre. I have vi but not vim installed.

Checking alternatives: /etc/alternatives/vi → /usr/bin/vim.tiny

So vi is vim.tiny, and it uses /etc/vim/vimrc.tiny.

And in vimrc.tiny you find the following line:

set compatible

Which is almost the only thing in this file. Note that in /etc/vim/vimrc it is using nocompatible.

So either install vim, or change the vimrc.tiny file, or create your own ~/.vimrc which should contain the line:

set nocompatible

On some systems, the nocompatible option is not available, or it may not fix the problem if a plugin breaks arrow key functionality. Here's a workaround...

Edit the .exrc file to include the following lines:

map! ^[OA ^[ka
map! ^[OB ^[ja
map! ^[OC ^[la
map! ^[OD ^[ha

Or, if the problem only exists in normal mode, you can change to nmap and skip the following a, as follows:

nmap! ^[OA ^[k

and so on.

Here's the key combinations needed to produce them (showing first one only):

map! <CTRL-V><Up-Arrow> <CTRL-V><ESC>ka

This escapes edit mode, moves in the wanted direction, and reenters edit mode. This is needed to overcome Vi reading the escape sequence as a sequence of literal <ESC><O><A>, etc.

Source: https://hea-www.harvard.edu/~fine/Tech/vi.html