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SIGNBIT(3) FreeBSD 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.
FreeBSD 14.0-RELEASE-p6 July 18, 2004 FreeBSD 14.0-RELEASE-p6