Why does fork() call this print statement?

Question

On this C program I get output I can't understand.

#include <stdio.h>

int main()
{
    printf("Hello World\n");
    printf("%d\n", fork());
    return 0;
}

It outputs:

Hello World
5
Hello World
0

My question, is why does it print "Hello World" twice? From my understanding it would print "Hello World" then call fork().

Does fork() start from the beginning of the program?

"Hello world" was cached, not written. So when second process exits it prints this messsage from the output buffer too. Add `fflush(stdout)` before forking. — , Nov 06 '17 at 19:13

score 0 · Answer 1 · answered Nov 06 '17 at 19:20

0

If you read the manual page fork returns a value to both the parent and child. And it doesn't start from the start of the program.

Please review the manual page for fork

answered Nov 06 '17 at 19:20

Ed Heal

1 Answers1