We have discussed Three methods of Zombie Prevention. This article is about one more method of zombie prevention.
Zombie Process: A process which has finished the execution but still has entry in the process table to report to its parent process is known as a zombie process. A child process always first becomes a zombie before being removed from the process table.
How Creating a Grandchild / Double Forking helps?
- The parent calls wait and creates a child. The child creates a grandchild and exits.
- The grandchild executes its instruction(task) and eventually it terminates. As the child has already exited, the grandchild will be taken care by init process.
- Init collect the exit status of grandchild. Hence the grandchild is not a zombie.
Note: Child is not a zombie as the parent called wait. Also in this case, the parent cannot verify the exit status of grandchild.
This article is contributed by Pramod Kumar. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.