opengroup [states](http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/time.h.html)
```C
int    tm_yday  Day of year [0,365]. 
```
shouldn't it be
```Make
-    int tm_yday;                  /* Days since January 0 [1, 366] */
+    int tm_yday;                  /* Days since January 1st [0, 365] */
```