mitchellh/vagrant — pull request #2752 by sferik (2014-01-03 16:32:48+00:00)
Title: Replace `exit 1` with `abort`

According to the documentation, Kernel.abort calls Kernel.exit(false). The failure status 1 is an implementation detail on Unix-like systems. In theory, a future system could exist where 1 indicates a successful exit and 0 indicates a failure.