RTOS interview questions [WITH ANSWERS]

RTOS interview questions are the subject of discussion in this article. Many for RTOS focus on their skills, forgetting that they will have to ace the interview session before putting their talent to work. But to help you a few, let’s talk on Rtos before looking at the RTOS interview questions. 

What is RTOS?

Rtos is a Real-time operating system. It is a real-time operating system (OS) for applications that handle data and events under strict time limitations. In a multitasking or multiprogramming context, an RTOS differs from a time-sharing operating system such as Unix, which controls the sharing of system resources through a scheduler, data buffers, or set task priority.

12 Common RTOS interview questions

RTOS interview questions

What exactly is a real-time system?

A time-bound system with well-defined fixed time limitations is known as a real-time system. The system will fail if the processing is not done within the stated boundaries.

  • What distinguishes RTOS from other operating systems?

RTOS provides services that allow jobs to be completed within predetermined time frames.

  • What exactly is a kernel?

A kernel is computer software at the heart of a computer’s operating system, controlling everything in it. It is one of the first programs to load on most systems when they boot up. The rest of the setup is taken care of, and software input/output requests co convert data-processing instructions for the central processor unit. Memory and peripherals such as keyboards, displays, printers, and speakers are all handled.

 

  • What exactly is a Core dump?

A core dump is a recording of the state of a computer program’s working memory certain point in time, usually when the program has crashed or otherwise ended abruptly.

A core dump is automatically triggered on many operating systems when a program throws a fatal exception. By extension, “to dump core” has come to indicate any fatal error in many circumstances, regardless of whether or not a record of the program memory exists. 

 

The terms “core dump,” “memory dump,” and simply “dump” have all become jargon for saving a huge amount of raw data for analysis or other uses.

 

  • What is the meaning of the term “volatile”?

The volatile keyword is simply a type qualifier that stops the compiler from optimizing the objects. You could also remark that the value of a volatile-qualified object can change at any time without the code taking any action. When a variable is qualified with the volatile qualifier, the compiler reloads the value from memory each time the program accesses it, preventing the variable from being cached into a register. The only way to check the value’s unanticipated change is to read it from memory.

 

  • What is a reentrant function, and what are its advantages and disadvantages?

 

A computer program or subroutine is referred to as reentrant in computing if it may be paused in the middle of its execution and safely called again (“reentered”) before its previous invocations complete execution. An internal activity like a jump or a call, or an external action like an interrupt or signal, could cause the interruption. The prior invocations will continue correct execution after the reentered invocation has been completed.

 

  • What is a semaphore?

Semaphore is simply a number variable. that is non-negative and shared between threads. it aids in solving variables is used to solve the critical section problems.

We look at more RTOS interview questions below

  • What is priority inversion, and how does it work?

In a circumstance when a low-priority job has a shared resource (for example, a semaphore) that a high-priority activity requires. This causes the high priority task’s execution to be halted until the low priority task releases the resource. The OS prevents this circumstance by raising the priority of the lowproi process until it completes the task and frees up resources.

 

  • Why is MFC not supported in Smartphones, even if this is a WinCE mobile?

MFC is merely a collection of classes developed utilizing Windows APIs to enable ease of use. Thus I don’t think it has anything to do with constrained hardware.

As a result, the correct response could be;

To create any mobile application, we only have a few APIs that users can utilize directly. In general, in embedded systems (including Soft RTOS), if you design your program with fewer (comfort)layers like MFC (and others if they exist: your application will be more efficient.

That is why a program developed in Assembly is more efficient than others even in today’s times.

Difference Between Stack Overflow And Heap Overflow

A stack overflow occurs when software tries to access memory outside the call stack’s reserved zone.

The subroutines that have been called and the local variables are stored in the call stack.

When too many functions are called and many local variables are used, overflow occurs.

 

  • What Is Priority Inversion and How Does It Work?

In a circumstance when a low-priority job has a shared resource (for example, a semaphore) that a high-priority activity requires. This causes the high priority task’s execution to be halted until the low priority task releases the resource. The OS prevents this circumstance by raising the priority of the lowproi process until it completes the job and frees up resources.

 

  • What is CE winCCE?

The initials “CE” in the name “Windows CE” do not stand for “Compact,” “Connectable,” “Compatible,” “Companion,” or “Efficient.” Still, they imply a number of the concepts around which Windows CE is created.

  • What is a graphical user interface?
  • GUI (Graphical User Interface) is a user interface that allows users to interact with the operating system via graphics. GUIs are produced rather than a command-line interface because they are more user-friendly, less complex, and easier to understand. GUIs are designed primarily to make things more efficient and easier to use. Instead of memorizing commands, users can click a button to carry out the task. Microsoft Windows, macOS, Apple’s iOS, and others are examples of graphical user interfaces.

Final thought

Drug tests are conditioned before any real time expert is employed. It is done to ensure that the work environment is drug free .So everybody must comply with the rules regulating the abuse of alcohol and the possession, sale, and use of illegal substances.