-int xstrtod (const char *str, const char **ptr, double *result,
- double (*convert) (char const *, char **));
+# include <stdbool.h>
+
+bool xstrtod (const char *str, const char **ptr, double *result,
+ double (*convert) (char const *, char **));
+bool xstrtold (const char *str, const char **ptr, long double *result,
+ long double (*convert) (char const *, char **));