Convertir un string en date en langage c

$ cat date2.c
#include <stdio.h>
#include <time.h>

main()
{
	struct tm tm;
	char *str="2009-11-19 13:33:47.51"; 

	strptime(str,"%Y-%m-%d %H:%M:%S", &tm);
	printf("%d/%d/%d %d:%d:%d\n", tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
}
$ 
$ make date2
cc     date2.c   -o date2
$ ./date2
2009/11/19 13:33:47
$ 
$ 

$ cat date3.c
#include <stdio.h>

main()
{
	int a, m, j ,h, min, s;
	char *str="2009-11-19 13:33:47.51"; 

	sscanf(str, "%d-%d-%d %d:%d:%d", &a, &m, &j, &h, &min, &s);
	printf("%d/%d/%d %d:%d:%d\n", a, m, j, h, min, s);
}
$ 
$ make date3
cc     date3.c   -o date3
$ ./date3
2009/11/19 13:33:47
$