unshift @_, qw( 3 6 nice -20 )
   unless  $_[0] =~ /^\d*\.?\d+$/;

##</code><code>##

breathe [-r RUN] [-s SUSPEND] [-n "NICE OPT"] CMD [ARG ...]
breathe [-r RUN] [-s SUSPEND] [-n] [NICE OPT] CMD [ARG ...]