FPCLASSIFY(3P)                                      POSIX Programmer's Manual                                     FPCLASSIFY(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       fpclassify - classify real floating type

SYNOPSIS
       #include <math.h>

       int fpclassify(real-floating x);


DESCRIPTION
       The  fpclassify()  macro  shall  classify  its  argument value as NaN, infinite, normal, subnormal, zero, or into another
       implementation-defined category. First, an argument represented in a format wider than its semantic type is converted  to
       its semantic type. Then classification is based on the type of the argument.

RETURN VALUE
       The  fpclassify()  macro  shall return the value of the number classification macro appropriate to the value of its argu-
       ment.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       isfinite(), isinf(), isnan(), isnormal(), signbit(), the Base Definitions volume of IEEE Std 1003.1-2001, <math.h>

COPYRIGHT
       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, Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                FPCLASSIFY(3P)