NAME
signbit —
determine whether a floating-point
number's sign is negative
LIBRARY
library “libm”
SYNOPSIS
#include
<math.h>
int
signbit(real-floating
x);
DESCRIPTION
The
signbit()
macro takes an argument of x and returns non-zero if
the value of its sign is negative, otherwise 0.
SEE ALSO
STANDARDS
The signbit() macro conforms to
ISO/IEC 9899:1999
(“ISO C99”).
HISTORY
The signbit() macro was added in
FreeBSD 5.1.