To display the line numbers when editing a file with vi simply type the following during the edit.

Once line numbers are set then to remove the listing of numbers down the left hand column type the following.

VI Example: Displaying Line Numbers

Useful VI references.

Learning the vi and Vim Editors

Arnold Robbins. O’Reilly Media, Inc. 2008, Paperback, 492 pages, $19.98

Hacking Vim

Kim Schulz. Packt Publishing 2007, Paperback, 228 pages, $35.94