C语言打印当前时间

#include <stdio.h>
#include <time.h>
char* getDateTime();

int main()
{
    char* nowtime = getDateTime();
    printf("%s\n", nowtime);
    return 0;
}

char* getDateTime()
{
    static char nowtime[20];
    time_t rawtime;
    struct tm* ltime;
    time(&rawtime);
    ltime = localtime(&rawtime);
    strftime(nowtime, 20, "%Y-%m-%d %H:%M:%S", ltime);
    return nowtime;
}