}
$opt{width} ||= $ENV{COLUMNS} || qx(tput cols) || 80 unless $opt{spark};
-$opt{color} //= -t *STDOUT; # enable on tty
+$opt{color} //= $ENV{NO_COLOR} ? 0 : -t *STDOUT; # enable on tty
$opt{'graph-format'} //= '-';
$opt{trim} *= $opt{width} / 100 if $opt{trimpct};
$opt{units} = [split //, ' kMGTPEZYyzafpn'.($opt{ascii} ? 'u' : 'μ').'m']
Force colored output of values and bar markers.
Defaults on if output is a tty,
disabled otherwise such as when piped or redirected.
+Can also be disabled by setting I<-C>
+or the I<NO_COLOR> environment variable.
=item -f, --field=(<number> | <regexp>)