Check_files sum of size from Files


i want to Monitor whether the sum of the size of a selection of files is larger than a threshold. This files must be from today.
i tryed this but the result shows me the size of each file and i dont know how i select the filter for today
/usr/local/nagios/libexec/check_nrpe -H HOST -n -c check_files -a path=F:\oracle\oradata\backup\UNIWARE\ pattern=. “filter=creation > -1m” “crit=size<50g” “max-depth=1”

Thanks for Help