http://www.hypermake.com/english/do.html
"DO.EXE is a set of very useful batch enhancements and command-line utilities. This version replaces a handful of old freeware exe programs which stopped running properly due to integer overflow. DO.EXE also works if the results are larger than 32 bits, e.g. free disk space larger than 2 or 4 GB."
Source: OS2.jp