ISFINITE(3P) POSIX Programmer's Manual ISFINITE(3P)
PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding
Linux manual page for details of Linux behavior), or the interface may
not be implemented on Linux.
NAME
isfinite - test for finite value
SYNOPSIS
#include <math.h>
int isfinite(real-floating x);
DESCRIPTION
The isfinite() macro shall determine whether its argument has a finite
value (zero, subnormal, or normal, and not infinite or NaN). First, an
argument represented in a format wider than its semantic type is con-
verted to its semantic type. Then determination is based on the type of
the argument.
RETURN VALUE
The isfinite() macro shall return a non-zero value if and only if its
argument has a finite value.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
fpclassify(), isinf(), isnan(), isnormal(), signbit(), the Base Defini-
tions 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, 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 .
IEEE/The Open Group 2003 ISFINITE(3P)