| ISFINITE(3) | Library Functions Manual | ISFINITE(3) | 
NAME
 isfinite — 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 converted 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 neither 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.
STANDARDS
 The isfinite() macro conforms to ISO/IEC 9899:1999 (“ISO C99”).