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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.

SEE ALSO
     finite(3), fpclassify(3), isnormal(3), math(3), signbit(3)

STANDARDS
     The isfinite() macro conforms to ISO/IEC 9899:1999 ("ISO C99").

NetBSD 10.99                    August 6, 2011                    NetBSD 10.99