1LROUND(3) Linux Programmer's Manual LROUND(3)
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6 lround, lroundf, lroundl, llround, llroundf, llroundl - round to near‐
7 est integer, away from zero
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10 #include <math.h>
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12 long int lround(double x);
13 long int lroundf(float x);
14 long int lroundl(long double x);
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16 long long int llround(double x);
17 long long int llroundf(float x);
18 long long int 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: _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or
25 cc -std=c99
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28 These functions round their argument to the nearest integer value,
29 rounding away from zero, regardless of the current rounding direction
30 (see fenv(3)).
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32 Note that unlike round(3), ceil(3), etc., the return type of these
33 functions differs from that of their arguments.
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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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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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54 These functions first appeared in glibc in version 2.1.
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57 C99, POSIX.1-2001.
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60 ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)
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63 This page is part of release 3.22 of the Linux man-pages project. A
64 description of the project, and information about reporting bugs, can
65 be found at http://www.kernel.org/doc/man-pages/.
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69 2008-08-11 LROUND(3)