Operating Systems · Question 10 · Medium
How many times is "Hi" printed when this C program runs? Assume every fork() call succeeds.
#include <stdio.h>
#include <unistd.h>
int main() {
if (fork() == 0)
fork();
printf("Hi\n");
return 0;
}- 2
- 4
- 3
- 8
Answer and explanation
Answer: C. 3
Explanation: The parent gets a non-zero value from fork(), so it skips the inner fork and prints once. The child gets 0 and calls fork() again, after which the child and the grandchild each print. That is 3 prints in total.
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