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SIGNBIT 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
NAME
signbit - test sign
SYNOPSIS
c99 [ flag... ] file... -lm [ library... ] #include <math.h> int signbit(real-floating x);
DESCRIPTION
The signbit() macro determines whether the sign of its argument value is negative. NaNs, zeros, and infinities have a sign bit.
RETURN VALUES
The signbit() macro returns a non-zero value if and only if the sign of its argument value is negative.
ERRORS
No errors are defined.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Standard |
| MT-Level MT-Safe |
SEE ALSO
fpclassify(3M), isfinite(3M), isinf(3M), isnan(3M), isnormal(3M), math.h(3HEAD), attributes(5), standards(5)