Need help in fork() diagram

Question

tomorrow is my exam and i have difficulty in understanding fork() diagrams, all what i want is to correct me
fork()&&fork()&&fork()

i used this diagram

but my teacher told me that this is wrong and if u draw me this tomorrow i will give u negative marks, and he me told that this is the right one.

klutt · Answer

fork()&&fork()&&fork() is equivalent to this:
if(fork()) {
    if(fork()) {
       fork();
    }
}

From the documentation for fork() you can read that it returns the pid of the child in the parent process, and 0 in the child process. So the second diagram is correct. No child process will invoke fork.

Tony Tannous · Answer

The fork() returns the pid of the child in parent address space, some non-negative value. While in the child address space, a 0 is returned.
The && operand doesn't evaluate the rhs if the lhs is false, which is the case in the child process.
After first fork
Parent

true && fork() && fork()

Child
      
          ---> never evaluated
    false && fork() && fork()

Need help in fork() diagram

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