cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ] #include <mathcw.h> extern int issnanf (float x); extern int issnan (double x); extern int issnanl (long double x); extern int issnanw (__float80 x); extern int issnanq (__float128 x); extern int issnanll (long_long_double x); extern int issnandf (decimal_float x); extern int issnand (decimal_double x); extern int issnandl (decimal_long_double x); extern int issnandll (decimal_long_long_double x);
NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.
On systems that lack support for both quiet and signaling NaNs, such as older versions of the Intel IA-32 architecture, and the Java Virtual Machine, this function returns 1 for any NaN.