I think the auto-all-the-things here was a making this a little
hard to follow, so replace these things that will be used in printf
with what they really are. And change the * lengths to ints.
should clear up the alerts.
1. When the wall time and cpu time rows has different units
e.x. running multiple cores
2. When duration is around 1E3 or 1E6 microseconds
printf("%6.2F", 999.995) gives 1000.00 which is 7 digits
In particular, this allows `true && time true`, or `true; and time true`,
and both `time not true` as well as `not time true` (like bash).
time is valid only as job _prefix_, so `true | time true` could call
`/bin/time` (same in bash)
See discussion in #6442