Modern Vim

Tip 26

Using Autocommands to Respond to Events

This tip comes in two parts. In the first part, you’ll try out some examples of autocommands to understand how they work. In the second part, you’ll look at some real examples of how autocommands can be useful, collected from other tips in this book.

Understanding Autocommands

Here’s a short sample Vim script that defines two autocommands:

autocmd-demo/autocmds-01.vim

augroup demo
  autocmd!
  autocmd BufReadPost * echo 'Reading: ' . expand('<afile>')
  autocmd BufWritePost * echo 'Writing: ' . expand('<afile>')
augroup END

Before we look at the syntax of these autocommands, let’s see how they behave. Open that script in a fresh instance of Vim:

$ cd code/autocmd-demo/
$ vim ...