This is a very roughly kitbashed version of NetBSD bc(1) for MS-DOS.  I have
not tested it very much, but on a basic level it does appear to work.

If it looks rather like GNU bc(1), that is not a coincidence: the same author
contributed bc to both GNU and NetBSD and the code is almost identical.  I
have only made the bare minimum of changes in order to get a reasonably sane
binary, once I had it running on Linux as part of another project.

S. V. Nickolas
Aug. 17, 2020

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