ISFINITE(3) BSD Library Functions Manual ISFINITE(3)NAMEisfinite — test for finite value
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <math.h>
int
isfinite(real-floating x);
DESCRIPTION
The isfinite() determines whether its argument x has a finite value. An
argument represented in a format wider than its semantic type is con‐
verted to its semantic type first. The determination is then based on
the type of the argument.
IEEE 754
It is determined whether the value of x is zero, subnormal, or normal,
and neither infinite nor NaN.
VAX
It is determined whether the value of x is true zero or finite, and nei‐
ther dirty zero nor ROP.
RETURN VALUES
The isfinite() macro returns a non-zero value if the value of x is
finite. Otherwise 0 is returned.
ERRORS
No errors are defined.
SEE ALSOfinite(3), fpclassify(3), isnormal(3), math(3), signbit(3)STANDARDS
The isfinite() macro conforms to ISO/IEC 9899:1999 (“ISO C99”).
BSD August 6, 2011 BSD