SIGNBIT(3) BSD Library Functions Manual SIGNBIT(3)
NAME
signbit -- determine whether a floating-point number's sign is negative
LIBRARY
Math Library (libm, -lm)
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
fpclassify(3), math(3)
STANDARDS
The signbit() macro conforms to ISO/IEC 9899:1999 (``ISO C99'').
HISTORY
The signbit() macro was added in FreeBSD 5.1.
BSD
July 18, 2004 BSD