Program to print Current time & day in C

#include 
#include 
int current_day(void)
{ struct tm *local;
 time_t t;

 t = time(NULL);
 local = localtime(&t);
 return local->tm_wday;
}
int main(int argc, char *argv[])
{
 printf("Today: %d\n", current_day());
 exit(0);
}