#include <stdio.h>
#include <string.h>

int main()
{
        char *dateSTR = "234234/345345/23455323";
        int dateINT[3], i;
        
        if ( sscanf(dateSTR, "%d/%d/%d", &dateINT[0], &dateINT[1], &dateINT[2]) == 3)
        {
                printf("Data correcta");
        } else {
                printf("Errado");
        }
        
        return 0;
}

Data correcta