NAME
nan() — string-to-NaN conversion function
SYNOPSIS
#include <math.h>
double nan(const char *tagp);
DESCRIPTION
The
nan()
function creates a quiet NaN from the specified string. The call
nan("n-char-sequence")
is equivalent to
strtod("NAN(n-char-sequence)", (char**) NULL).
The call
nan("")
is equivalent to
strtod("NAN()", (char**) NULL).
If
tagp
does not point to an
n-char-sequence
string, the result NaN's content is unspecified.
The ISO/ANSI C committee has approved the
nan()
function for inclusion in the C9X draft standard.
To use this function, compile either with the default
-Ae
option or with the
-Aa
and
-D_HPUX_SOURCE
options. Make sure your program includes
<math.h>.
Link in the math library by specifying
-lm
on the compiler or linker command line.
RETURN VALUE
The
nan()
function returns a quiet NaN.
ERRORS
No errors are defined.
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