[Simh] pdp11 and unix

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On Sat, 27 Feb 2016 17:32:19 -0500
Paul Koning <paulkoning at comcast.net> wrote:

> Decimal did show up at times even into the 1960s, for example in the IBM
> 1620.  But it never made all that much sense; converting between binary
> and decimal is quite easy even in those very old machines.  The one
> plausible application area is business data processing where the
> arithmetic is trivial and most of the work is I/O or other non-arithmetic
> operations.

IBM S/360 (1964) and follow-ons have all had hardware support for decimal
and COBOL and PL/I on these platforms have always had native suport for the
data type.

As you might expect decimal arithmetic is used extensively in financial
transactions and reporting since there is no problem of conversion. Money
can be represented exactly rather than approximately as with floating
point. Most banks still run their financial transactions on IBM hardware
and OS for that reason among others.