Only close handles that are set to a valid handle value
Only close handles that are set to a valid handle value

docwhat/mixlib-shellout,juliandunn/mixlib-shellout,BackSlasher/mixlib-shellout,chef/mixlib-shellout,juliandunn/mixlib-shellout,docwhat/mixlib-shellout,BackSlasher/mixlib-shellout,chef/mixlib-shellout