Convert to Integer
Converts a decimal floating-point value to a 64-bit signed binary integer, using a specified rounding mode.
long long __d64_to_long_long_rounding (_Decimal64, long rounding_mode);
long long __d128_to_long_long_rounding (_Decimal128, long rounding_mode);
The input value converted to a long long, using the specified rounding mode (not always rounded towards zero as a cast or implicit conversion would be).
These functions temporarily override the rounding mode in effect for the current operation.