double longs

[Chuck_M_Grandgent at cup.portal.com]

I'm look for leads on "C" source for doing simple arithmetic 
efficiently with "double longs" - that is, I need twice the
integer precision of a long, and for Intel chip architecture
to boot (not a bad idea - 'to boot' Intel arch.).
Reals just don't hack it for what I need to do.
"dlong" add and subtract are pretty trivial, you could maintain
two longs and do the carry/borrow yourself, but multiply and
divide appear more difficult to do efficiently.
If had "dlongs" could get nice precision (by doing appropriate
scaling) without attendant complications of floating point
packages.
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sun!portal!cup.portal.com!chuck_m_grandgent     K1OM
AEG Modicon Industrial Automation Systems Group
North Andover, Mass.
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