Originální popis anglicky:
signbit - test sign
Návod, kniha: POSIX Programmer's Manual
#include <math.h>
int signbit(real-floating
x);
The
signbit() macro shall determine whether the sign of its argument
value is negative. NaNs, zeros, and infinities have a sign bit.
The
signbit() macro shall return a non-zero value if and only if the sign
of its argument value is negative.
No errors are defined.
The following sections are informative.
None.
None.
None.
None.
fpclassify() ,
isfinite() ,
isinf() ,
isnan() ,
isnormal() , the Base Definitions volume of
IEEE Std 1003.1-2001,
<math.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html
.
