Operating Systems · Question 23 · Medium
How many times is "A" printed when this C program runs? Assume every fork() call succeeds.
#include <stdio.h>
#include <unistd.h>
int main() {
for (int i = 0; i < 2; i++) {
fork();
printf("A\n");
fflush(stdout);
}
return 0;
}- 4
- 8
- 3
- 6
Answer and explanation
Answer: D. 6
Explanation: In the first iteration the original process forks, and 2 processes print A. In the second iteration each of those 2 forks, and 4 processes print A. Total = 2 + 4 = 6. fflush ensures no buffered output is copied into a child.
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