NAME

nan, nanf, nanl — return quiet NaN

LIBRARY

Math Library (libm, -lm)

SYNOPSIS

#include <math.h>

double
nan(const char *tagp);

float
nanf(const char *tagp);

long double
nanl(const char *tagp);

DESCRIPTION

The call nan("n-char-sequence") is equivalent to the call strod("NAN(n-char-sequence)", NULL). The call nan("") is equivalent to the call strod("NAN()", NULL).

The nanf() and nanl() functions are equivalent to nan() but substituting strtof() and strtold(), respectively.

RETURN VALUES

SEE ALSO

math(3), strtod(3)

STANDARDS

The nan(), nanf(), and nanl() functions conform to ISO/IEC 9899:1999 (“ISO C99”).