round, roundf, roundl - round to nearest integer, away from zero
These functions return the rounded integer value.
x is integral, +0, -0, NaN, or infinite,
itself is returned.
No errors occur. POSIX.1-2001 documents a range error for overflows, but see NOTES.
These functions first appeared in glibc in version 2.1.
C99, POSIX.1-2001, POSIX.1-2008.
POSIX.1-2001 contains text about overflow (which might set
errno to ERANGE, or raise an
FE_OVERFLOW exception). In practice, the result cannot
overflow on any current machine, so this error-handling stuff is just
nonsense. (More precisely, overflow can happen only when the maximum
value of the exponent is smaller than the number of mantissa bits. For
the IEEE-754 standard 32-bit and 64-bit floating-point numbers the
maximum value of the exponent is 128 (respectively, 1024), and the
number of mantissa bits is 24 (respectively, 53).)
If you want to store the rounded value in an integer type, you probably want to use one of the functions described in lround(3) instead.
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