When running a query (in this case a Drill query over a large Hive table), pressing CTRL+C to cancel a query and exit the shell causes a cancellation message in sqlline.log but causes the SQLLINE shell to hang. CTRL-Z then needs to be pressed and the SQLLINE process needs to be killed manually. A CTRL+C keyboard interrupt should cancel the query and provide a new empty query line in the shell. A further CTRL-C keyboard press should exit the SQLLINE shell.
sqlline.log cancellation entry:
2014-09-05 14:16:13,852 [SIGINT handler] DEBUG o.a.drill.exec.client.DrillClient - Cancelling query b0b36fa7-051e-484e-bb42-f57613401834
2014-09-05 14:16:13,858 [Client-1] DEBUG org.apache.drill.jdbc.DrillResultSet - Result arrived QueryResultBatch [header=query_state: CANCELED