From c51952a68db5b26945b014e857843b77ea2ab6b6 Mon Sep 17 00:00:00 2001
From: jabclab <jake.clarkson@digitalanimal.com>
Date: Thu, 26 Sep 2013 10:13:44 +0100
Subject: [PATCH] Resolving #2194 (Ansible buffering output if run as
 subprocess)

---
 plugins/provisioners/ansible/provisioner.rb | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/plugins/provisioners/ansible/provisioner.rb b/plugins/provisioners/ansible/provisioner.rb
index 0fdad491d..71284fe0e 100644
--- a/plugins/provisioners/ansible/provisioner.rb
+++ b/plugins/provisioners/ansible/provisioner.rb
@@ -41,7 +41,10 @@ module VagrantPlugins
         command << {
           :env => {
             "ANSIBLE_FORCE_COLOR" => "true",
-            "ANSIBLE_HOST_KEY_CHECKING" => "#{config.host_key_checking}"
+            "ANSIBLE_HOST_KEY_CHECKING" => "#{config.host_key_checking}",
+            # Ensure Ansible output isn't buffered so that we receive ouput
+            # on a task-by-task basis.
+            "PYTHONUNBUFFERED" => 1
           },
           :notify => [:stdout, :stderr],
           :workdir => @machine.env.root_path.to_s