Linux VI Command – Set Line Number

The “Set Number” command in the VI (visual instrument) text editor seems may not seem like the most useful command.  However, it is more useful than it appears.  Using the “set number” command is a visual aid, which facilitates navigation within the VI editor. 

To Enable Line Number In the VI Editor

The “set Number” command is used to make display line numbers, to enable line numbers:

  • Press the Esc key within the VI editor, if you are currently in insert or append mode.
  • Press the colon key “:”, which will appear at the lower-left corner of the screen.
  • Following the colon enter “set number” command (without quotes) and press enter.

A column of sequential line numbers will then appear at the left side of the screen. Each line number references the text located directly to the right. Now you will know exactly which line is where and be able to enter a colon and the line number you want to move to and move around the document lines with certainty.

To Disable Line Number In the VI Editor

When you are ready to turn offline numbering, again follow the preceding instructions, except this time, enter the following line at the : prompt:

  • Press the Esc key within the VI editor, if you are currently in insert or append mode.
  • Press the colon key “:”, which will appear at the lower-left corner of the screen.
  • Following the colon enter “set nonumber” command (without quotes) and press enter.

To Make The Line Number Enable When You Open VI:

Normally, vi will forget the setting you’ve chosen once you’ve left the editor. You can, however, make the “set Number” command take effect automatically whenever you use vi on a user/account, enter the “set Number” command as a line in the .exrc file in your home directory.