open (SUM2,">$ARGV[0].sum.sorted");

my @records;
{
    local $/ = /^\s+$/;
# Step through text file from one blank line to the
# next, grabbibg everything in between all at once.      
    open IN2, "$ARGV[0].sum" or die "Cannot open data file.\n$!";
    while ( my $record = <IN2> ) {
        my @kv_pairs = split /\n/, $record;
# Split each record into its <always 9> lines, and store
# each line as an array element.
        push @records, [@kv_pairs];
# Create an anonymous array that is a copy of @kv_pairs.
# Push the anonymous array containing a complete set
# of keys/values for a given record into the @records array
# as an array of arrays.
    }
    close IN2;
}

print STDERR 'Record count: ', scalar @records;

# ST sort...

my @sorted_recs = map { $_->[0] }
        sort { $a->[1] <=> $b->[1] }
        map { [ $_, (split /=\s+/,$_->[4])[1] ] }
# The 5th line [4] of each record has a decimal number
# after the "=".  Grab that number and sort all records
# by those numbers.
        @records;

print SUM2 foreach @sorted_recs;

close IN2;
close SUM2;