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lround(3)                  Library Functions Manual                  lround(3)

NAME
       lround,  lroundf, lroundl, llround, llroundf, llroundl - round to near-
       est integer

LIBRARY
       Math library (libm, -lm)

SYNOPSIS
       #include <math.h>

       long lround(double x);
       long lroundf(float x);
       long lroundl(long double x);

       long long llround(double x);
       long long llroundf(float x);
       long long llroundl(long double x);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       All functions shown above:
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION
       These functions round their argument  to  the  nearest  integer  value,
       rounding halfway cases away from zero, regardless of the current round-
       ing direction (see fenv(3)).

       Note that unlike the round(3) and ceil(3), functions, the  return  type
       of these functions differs from that of their arguments.

RETURN VALUE
       These functions return the rounded integer value.

       If  x  is a NaN or an infinity, or the rounded value is too large to be
       stored in a long (long long in the case of the ll* functions),  then  a
       domain error occurs, and the return value is unspecified.

ERRORS
       See  math_error(7) for information on how to determine whether an error
       has occurred when calling these functions.

       The following errors can occur:

       Domain error: x is a NaN or infinite, or the rounded value is too large
              An invalid floating-point exception (FE_INVALID) is raised.

       These functions do not set errno.

VERSIONS
       These functions were added in glibc 2.1.

ATTRIBUTES
       For an  explanation  of  the  terms  used  in  this  section,  see  at-
       tributes(7).

       ┌────────────────────────────────────────────┬───────────────┬─────────┐
       │InterfaceAttributeValue   │
       ├────────────────────────────────────────────┼───────────────┼─────────┤
       │lround(), lroundf(), lroundl(), llround(),  │ Thread safety │ MT-Safe │
       │llroundf(), llroundl()                      │               │         │
       └────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS
       C99, POSIX.1-2001, POSIX.1-2008.

SEE ALSO
       ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)

Linux man-pages 6.03              2022-12-15                         lround(3)

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