1LROUND(3)                  Linux Programmer's Manual                 LROUND(3)
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NAME

6       lround,  lroundf, lroundl, llround, llroundf, llroundl - round to near‐
7       est integer
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SYNOPSIS

10       #include <math.h>
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12       long lround(double x);
13       long lroundf(float x);
14       long lroundl(long double x);
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16       long long llround(double x);
17       long long llroundf(float x);
18       long long llroundl(long double x);
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20       Link with -lm.
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22   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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24       All functions shown above:
25           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
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DESCRIPTION

28       These functions round their argument  to  the  nearest  integer  value,
29       rounding halfway cases away from zero, regardless of the current round‐
30       ing direction (see fenv(3)).
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32       Note that unlike the round(3) and ceil(3), functions, the  return  type
33       of these functions differs from that of their arguments.
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RETURN VALUE

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

43       See  math_error(7) for information on how to determine whether an error
44       has occurred when calling these functions.
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46       The following errors can occur:
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48       Domain error: x is a NaN or infinite, or the rounded value is too large
49              An invalid floating-point exception (FE_INVALID) is raised.
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51       These functions do not set errno.
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VERSIONS

54       These functions first appeared in glibc in version 2.1.
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ATTRIBUTES

57       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
58       tributes(7).
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60       ┌────────────────────────────────────────────┬───────────────┬─────────┐
61       │Interface                                   │ Attribute     │ Value   │
62       ├────────────────────────────────────────────┼───────────────┼─────────┤
63       │lround(), lroundf(), lroundl(), llround(),  │ Thread safety │ MT-Safe │
64       │llroundf(), llroundl()                      │               │         │
65       └────────────────────────────────────────────┴───────────────┴─────────┘
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CONFORMING TO

68       C99, POSIX.1-2001, POSIX.1-2008.
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SEE ALSO

71       ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)
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COLOPHON

74       This page is part of release 5.13 of the Linux  man-pages  project.   A
75       description  of  the project, information about reporting bugs, and the
76       latest    version    of    this    page,    can     be     found     at
77       https://www.kernel.org/doc/man-pages/.
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81                                  2021-03-22                         LROUND(3)
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