язык точной арифметики (precision arithmetic language)
Параметры (Options)
The bc utility shall conform to the Base Definitions volume of
POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines.
The following option shall be supported:
-l (The letter ell.) Define the math functions and
initialize scale to 20, instead of the default zero;
see the EXTENDED DESCRIPTION section.
