Pac is a slightly overambitious visual calculator for Unix systems.
In spite of its minor structural problems, pac is the
"everything you ever wanted in a calculator" calculator, providing:

o   16 cells nonvolatile memory (checkbook balance, phone numbers, etc.)
o   asynchronous real-time clock
o   separate checkbook balancer window (for summing lists of numbers)
o   ASCII to decimal to octal to hex translation (find out what ^M is)
o   22 predefined conversions (metric, temperature, etc.)
o   user-definable, non-volatile conversions (dollar to yen, etc.)
o   compound interest/mortgage payment solver (play the "what if?" game)
o   amortization schedule (monthly payment list) file writer
o   function help window (type "help" or just "?" or "help [subject]")
o   optional automatic calculator session recording to files
o   trigonometric functions
o   number base conversions (independent in/out bases, between 2 and 16)
o   programmable precision: btw 0 and 32 digits past the decimal point
o   bitwise AND, OR, NOT, XOR, TWOSCOMP
o   fully automatic and accessible push/pop stack memory
o   pi, planck, parallax, parsec... 30 math/physical constants in all
o   macro tokens from "atto" to "exa" (for ex: "356 micro + 125 milli")
o   predefined percent calculations (for ex: "65.7 p[ercent]of 290")

The pac process forks pipes to the 'bc' Unix calculator.
The posted source has been successfully compiled and tested on:
Pyramid 90x, VAX 11-785, Apollo Domain-IX, Sun SPARCstation 1,
AT&T 6300+, Xenix286, DEC 8600.

Pac will NOT work on Sun2 or Sun3 computers due to insoluble problems
in their implementation of "curses".

