Open System Services System Calls Reference Manual (G06.29+, H06.08+, J06.03+)

math(4) OSS System Calls Reference Manual
NAN For IEEE floating-point environments only, specifies a constant expression of
type float representing a quiet not-a-number (NaN).
The following macros are defined for number classification. They represent mutually-exclusive
kinds of floating-point values and expand to integer constant expressions with distinct values:
FP_INFINITE
Infinity.
FP_NAN NaN.
FP_NORMAL Normalized.
FP_SUBNORMAL
Denormalized.
FP_ZERO Zero.
The following macros expand to integer constant expressions whose values are returned by
ilogb(x):
FP_ILOGB0 Expands to an integer constant expression whose value is returned by ilogb(x)if
x is zero. The value of FP_ILOGB0 is {INT_MIN}.
FP_ILOGBNAN
Expands to an integer constant expression whose value is returned by ilogb(x)if
x is NaN. The value of FP_ILOGBNAN is either {INT_MIN}.
The following macros are defined to identify the error handling method supported by the math.h
functions:
MATH_ERRNO
Indicates support for the ISO/IEC C99 errno specification.
MATH_ERREXCEPT
Indicates support for the ISO/IEC exception flag specification.
math_errhandling
Defined to be MATH_ERRNO in all situations.
RELATED INFORMATION
Files: float(4).
STANDARDS CONFORMANCE
This function conforms to the ISO/IEC 9899:1999 standard.
This function conforms to the IEEE Std 1003.1, 2004 Edition.
Support for Tandem floating-point values is an HP extension to the standards.
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