how many process created?

Question

Consider the following Pseudo code

main()  
{
    int t1=0,t2=0,t3=0;
    t1=fork();
    t2=fork();
    if(t1!=0)
    {
        t3=fork();
        printf("0");
    }  
}  

Find the total number of processes that will be created by the above program execution. 

Comments

is the total no of processes = 6 and no of child process = 5?

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Let the parent process be denoted by P.

Here, the concept of copy on write is used and hence, P and C3 share the same value of t1.

Now, as you can see , the processes at the leaves are P, C1, C2, C3, C4, C5

But, parent process is the process that started the program execution. they have asked No. of processed created by above program execution. How can parent process be created by above program execution?

$\therefore$ No of processed created by above program excution = 5

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No. Of processes created by program is 1parent + 5child processes = 6 processes.
The answer is 6, not 5.

Answer 1

P

                           P                C

                P              C1      C       C2

       P       C3     C1      C4

So total 6 processes P C C1 C2 C3 C4

After first fork statement execution fork returns 0 to child and id of child to parent process P.Same happens for second fork so now 4 process are there .Now t1is not zero for P and C1 so they will execute fork..sonow there will be 6 process

Answer 2

Is it correct ans

total =1(Parent)+5(Child)=6

Comments

Ans 6 is correct.

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this will be the best solution

Answer 3

Total process will be 8 including main.

Newly created child process will be 7.

Since for n fork() calls total child process will be 2ⁿ - 1

Comments

Thats for n fork calls in a loop or without any intermediate condition.

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Sorry sir. It's my fault. i thought the condition is like (t1==0).

Thanks for correcting me

Answer 4

Including parent process, answer is 6