Rename examples/tips to examples/pubsub
diff --git a/examples/pubsub/README b/examples/pubsub/README
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+C++ Client implementation for Cloud Pub/Sub service
+(https://developers.google.com/apis-explorer/#p/pubsub/v1beta1/).
+
+"Google Cloud Pub/Sub" API needs to be enabled at
+https://console.developers.google.com/project to open the access for a client.
+Select the project name, select the "APIs" under "APIs & auth", and turn
+on "Google Cloud Pub/Sub" API.
+
+To run the client from Google Compute Engine (GCE), the GCE instance needs to
+be created with scope "https://www.googleapis.com/auth/cloud-platform" as below:
+
+gcloud compute instances create instance-name
+ --image debian-7 --scopes https://www.googleapis.com/auth/cloud-platform
+
+Google TLS cert is required to run the client, which can be downloaded from
+Chrome browser.
+
+To run the client from GCE:
+make pubsub_client
+GRPC_DEFAULT_SSL_ROOTS_FILE_PATH="Google TLS cert" bins/opt/pubsub_client
+ --project_id="your project id"
+
+A service account credential is required to run the client from other
+environments, which can be generated as a JSON key file from
+https://console.developers.google.com/project/. To run the client with a service
+account credential:
+
+GRPC_DEFAULT_SSL_ROOTS_FILE_PATH="Google TLS cert" bins/opt/pubsub_client
+ --project_id="your project id"
+ --service_account_key_file="absolute path to the JSON key file"