If the file is not present on the client or if the command would fail, {HEAD ~ the present invention} ignores {TAIL ~ the command} and does not attempt to execute it later 
ignores
If the file is not present on the client or if the command would fail , { HEAD ~ the present invention } ignores { TAIL ~ the command } and does not attempt to execute it later
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH