vagrant

https://github.com/mitchellh/vagrant

Ruby

Vagrant is a tool for building and distributing development environments.

Vagrant::Environment#active_machines

Returns a list of machines that this environment is currently
managing that physically have been created.

An "active" machine is a machine that Vagrant manages that has
been created. The machine itself may be in any state such as running,
suspended, etc. but if a machine is "active" then it exists.

Note that the machines in this array may no longer be present in
the Vagrantfile of this environment. In this case the machine can
be considered an "orphan." Determining which machines are orphan
and which aren't is not currently a supported feature, but will
be in a future version.

Source | Google | Stack overflow

Edit

git clone [email protected]:mitchellh/vagrant.git

cd vagrant

open lib/vagrant/environment.rb

Contribute

# Make a new branch

git checkout -b -your-name--update-docs-Vagrant--Environment-active_machines-for-pr

# Commit to git

git add lib/vagrant/environment.rbgit commit -m "better docs for Vagrant::Environment#active_machines"

# Open pull request

gem install hub # on a mac you can `brew install hub`

hub fork

git push <your name> -your-name--update-docs-Vagrant--Environment-active_machines-for-pr

hub pull-request

# Celebrate!