Example of passing a host environment variable through to a guest, using Vagrant script provisioner

Vagrantfile

# -*- mode: ruby -*-
# vi: set ft=ruby :

# test setting a guest environment variable based on a host environment variable
# if FOO_BAR is set locally, create command to add it to .profile in the guest

env_var_cmd = ""
if ENV['FOO_BAR']
  value = ENV['FOO_BAR']
  env_var_cmd = <<CMD
echo "export FOO_BAR=#{value}" | tee -a /home/vagrant/.profile
CMD
end

script = <<SCRIPT
#{env_var_cmd}
SCRIPT

VAGRANTFILE_API_VERSION = "2"
Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
  config.vm.box = "hashicorp/precise64"
  config.vm.hostname = "envtest"
  config.vm.provision :shell, :inline => script
  config.vm.provider "virtualbox" do |vb|
  #   vb.gui = true
     vb.name = "envtest"
     vb.customize ["modifyvm", :id, "--memory", "1000"]
  end
end

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