value printed is actually the optimized (i.e., the non-slow, not-on-the-fly
zero fills percentage) except in overflow cases. Describe it as %ozfod
in the display. Move the field descriptor 1 to the left so that there
is space for 5 characters after the % sign (this leaves no space between
the number and the descriptor but the % character serves well as a
separator).
Fixed integer overflow at z.ozfod = UINT_MAX/100 in the calculation of
%ozfod. This value can be reached just a few hours or minutes after
booting, so %ozfod was usually garbage in boot mode. Now %ozfod is
correct in boot mode for a few days or hours.
Print a non-dummy %ozfod when the division for it isn't division by 0
instead of when the result will be less than 100%. A result of 100%
may be correct, though a result of more than 100% indicates overflow
of one or both counters.