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

6       trunc, truncf, truncl - round to integer, toward zero
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SYNOPSIS

9       #include <math.h>
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11       double trunc(double x);
12       float truncf(float x);
13       long double truncl(long double x);
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15       Link with -lm.
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17   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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19       trunc(), truncf(), truncl():
20           _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
21           _POSIX_C_SOURCE >= 200112L;
22           or cc -std=c99
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DESCRIPTION

25       These functions round x to the nearest integer not larger  in  absolute
26       value.
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RETURN VALUE

29       These functions return the rounded integer value.
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31       If x is integral, infinite, or NaN, x itself is returned.
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ERRORS

34       No errors occur.
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VERSIONS

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

40   Multithreading (see pthreads(7))
41       The trunc(), truncf(), and truncl() functions are thread-safe.
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CONFORMING TO

44       C99, POSIX.1-2001.
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NOTES

47       The  integral  value  returned  by  these functions may be too large to
48       store in an integer type (int, long,  etc.).   To  avoid  an  overflow,
49       which  will  produce undefined results, an application should perform a
50       range check on the returned value before assigning  it  to  an  integer
51       type.
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SEE ALSO

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

57       This  page  is  part of release 3.53 of the Linux man-pages project.  A
58       description of the project, and information about reporting  bugs,  can
59       be found at http://www.kernel.org/doc/man-pages/.
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63                                  2013-06-21                          TRUNC(3)
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