__vfprintf
ret = __vfprintf(&f, fmt, ap);
int __vfprintf(FILE *, const char *, __va_list);
ret = __vfprintf(&f, fmt, ap);
ret = __vfprintf(&f, fmt, ap);
ret = __vfprintf(&f, fmt, ap);
if ((ret = __vfprintf(&f, fmt, ap)) < 0)
ret = __vfprintf(&fake, fmt, ap);
ret = __vfprintf(fp, fmt0, ap);
ret = __vfprintf(&f, fmt, ap);
ret = __vfprintf(&f, fmt, ap);