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

int main() {
    int buflen = 1 << 20;
    char* buf = malloc(buflen);
    FILE* pf = fopen("/dev/null", "w");
    clock_t start;
    int i;
    unsigned long long int written = 0;
    memset(buf, 0, buflen);
    start = clock();
    while (((float)(clock() - start)) / CLOCKS_PER_SEC < 0.95) {
        for (i = 0; i < 1000; ++i) {
            written += fwrite(buf, 1, buflen, pf);
        }
    }
    fclose(pf);
    free(buf);
    printf("time taken: %fs, bytes written: %llu\n",
        ((float)(clock() - start)) / CLOCKS_PER_SEC, written);
    return 0;
}