Fig 1: Angelina Jolie with her 3 adopted kids who were orphans

Orphans in the real world are very unfortunate victims of fate. Loosing parents is very unfortunate and exposes a child to unforeseen many other problems. There are many human problems we may solve like poverty or hunger but we can never have a world where no child becomes an orphan and looses parent’s love and care.

Real world scenarios are to some extent reflected in the linux operating system. There are processes in linux that also become orphans i.e. the parent process of the child process terminates, but the child is still executing. This article is not intended to give…


In my previous article, I wrote about how CPU schedules multiple processes using Time Slicing. We saw the output of how the print statements were intertwined. Now the question arises, what if we want one process to finish first, only then the second process to execute? In this article, I would like to show how to achieve that, i.e. Process Synchronization using the wait() system call.

Process Synchronization

Ensuring that the OS finishes execution of one process and only then executes another process is known as Process Synchronization.

Process Synchronization can be achieved using a System Call wait().



As a Computer Science graduate and a Software Professional, I have to interact with computers every day and been doing so for a long time. On the surface, we interact with so many applications which are nothing but individual processes being executed on the CPU. But how does CPU actually handle that is something that I would like to showcase in this article.

Time Slicing

Linux is a multi process OS. That means that OS has the ability to execute multiple processes. Does that mean that multiple processes are executing simultaneously? Well, the answer is NO, CPU at any…

Fig 1: Walking Dead Series (from internet)

The first time I heard about a Zombie process, I thought it was a joke. Because if anything that comes to mind on hearing the word zombie are the different movies or series showing the walking dead. Zombies are shown as attacking living beings resulting in an existential crisis for humans. It was only on further reading that I could understand why certain processes are called zombie processes. In this article I would like to go over what a zombie process is and how to create them.

The zombie process, have something in common with their namesake, so before looking…

Output of ls -l command

One of the first operation that any linux user performs is to list the contents of the directory that the user is in, using the ‘ls command. This simple command to list the contents of a directory also happens to be one of the favorite question that gets asked in system interviews. The question is kind of phrased like: “What happens when a user types ls -l foo* in the terminal”? The answer that the candidate gives, demonstrates the depth of the candidate’s understanding or knowledge of the linux kernel. There are few articles that try to answer the question…

Anyone who has read Operating Systems, comes across the concept of Deadlock. We come across several articles giving the definition and listing the 4 necessary conditions for deadlock. I felt there’s a dearth of articles, using a simple code example to demonstrate the deadlock and the 4 conditions. In this article, I would like to present a code demonstrating the 4 conditions that result in deadlock and give a walkthrough of the code.

To start off, I would like to first give the definition of ‘Deadlock’ and the 4 conditions, which result in a deadlock happening in a system. …

Kartik Siddhabathula

Sr. SDET, Starbucks | Previously Asst Prof | Love traveling, reading history and stories from around the world | Selenophile | Photography.

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