#include #include #include long long llround (double x) { /* Add +/- 0.5, then round towards zero. */ double tmp = trunc (x + (x >= 0.0 ? 0.5 : -0.5)); if (!isfinite (tmp) || tmp > (double)LONG_LONG_MAX || tmp < (double)LONG_LONG_MIN) { errno = ERANGE; /* Undefined behaviour, so we could return anything. */ /* return tmp > 0.0 ? LONG_LONG_MAX : LONG_LONG_MIN; */ } return (long long)tmp; }