dgsh-merge-sum − merge key value pairs, summing the values
dgsh-merge-sum file ...
dgsh-merge-sum will read key, value pairs from the files specified in its standard input, and print the input records merged together according to the value of the key. The input files should be sorted according to the key’s value. Records with the same key will have their values summed, and a single corresponding record will be printed. Whitespace is used as the separator. Leading whitespace is not taken into account when parsing fields. Thus dgsh-merge-sum can process multiple files generated by uniq -c, and merge them into one.
Diomidis Spinellis — <http://www.spinellis.gr>