my ($Month,$Period) = @_;
# exit if -m is set and not like YYYY-MM
die "$MySelf: E: Wrong date format - use '$MySelf -m YYYY-MM'!\n" if not &CheckMonth($Month);
+ # warn if -m and -p is set
+ warn "$MySelf: W: Time period assigned by '-p' takes precendece over month assigned by '-m'.\n" if ($Month && $Period);
# default: set -m to last month
$Month = &LastMonth if (!defined($Month) and !defined($Period));
# set $StartMonth, $EndMonth