printing ppid,child pid,pid

Applications Programming
1

question: for the below program
i just printed the value for pid, child pid and parent pid
why does it give me 6 values? i assume ppid is 28086
but can't figure out why there are 5 values printed instead of just two!
can someone comment on that!

#include<stdio.h>
#define DIM 8
int main()
{
int pid, i, ans;
int arr[DIM] = {1,2,3,4,5,6,7,8};

    pid = fork\(\);
    printf\("%d\\n",pid\);
    printf\("%d\\n",getpid\(\)\);
    printf\("%d\\n",getppid\(\)\);

}

the output is
$./a.out
0
28873
28872
28873
28872
28086

2

Remember what fork() does! Both parent and child each printed three lines.

3

perderabo,
yeah it makes sense that both child and process will execute the 3 staments, giving 6 results.
is the output in order of child,child,child,parent,parent,parent
now can u correct me if i m wrong here

0 - is the return int value that is always passed to the child to the child
this one is executed by printf("%d\n",pid);

28873 - is the pid of the child which is contained in the parent
this also executed by printf("%d\n",getpid());

28872 - is the pid of the parent
it is executed by printf("%d\n",getppid());

now running for parent
28873 - is the pid of the child
it is executed by printf("%d\n",pid);

28872 - is the pid of the parent that makes the child here
it is executed by printf("%d\n",getpid());

28086 - is the pid of the shell running this program
it is executed by printf("%d\n",getppid());

arrrrrrrrgh:confused: i am confuuuuuuuused!
Hope i got that right :frowning:
Sorry i am slow and ask too many questions:(

4

perderabo
actually i jus figured it out! thanks to you. you were a great help!
Cheers
a25khan:cool: