#include <stdio.h>
#include <time.h>

int main(int argc, char **argv)
{
    time_t timeNow;
    struct tm* time_info;
    time(&timeNow);
    time_info = localtime(&timeNow);
    char timeStr[sizeof"HH:MM:SS"];
    strftime(timeStr, sizeof(timeStr), "%H:%M:%S", time_info);
    printf("Time now: %s\n", timeStr);

    // add 10 seconds:
    timeNow += 10;
    time_info = localtime(&timeNow);
    strftime(timeStr, sizeof(timeStr), "%H:%M:%S", time_info);
    printf("New time: %s\n", timeStr);

    return 0;
}