Linux System Programming Techniques & Concepts

Based on your summary of frequently asked questions in a technical round for someone who writes C/C++/System Programming on their resume, it's clear that the interviewer is looking to assess a candidate's depth and breadth of knowledge in various areas related to system programming and the C language. Here are some additional insights into the types of questions that might be asked, categorized by experience level:

For 1–3 yrs of experience:

• Basic understanding of pointers and data structures.
• Familiarity with common system calls and their usage.
• Knowledge of memory management concepts at a high level.
• Debugging tools and techniques for C programs, especially in the context of memory corruption issues.

For 4–6 yrs of experience:

• A deeper understanding of memory allocation and management, including virtual memory and swap space.
• In-depth knowledge of Inter-Process Communication (IPC) mechanisms like pipes, message queues, shared memory, and semaphores.
• Proficiency in writing portable and robust code, with an understanding of system-specific differences.
• Experience with concurrency and synchronization primitives, and a good grasp of threading libraries.

For 7+ yrs of experience:

• Design and architecture knowledge, such as designing a thread library or memory allocation scheme.
• Strategic decisions on when to use processes versus threads.
• Advanced knowledge of memory allocation strategies and how to implement custom allocators.
• Understanding of performance profiling tools like ValGrind and how they work.
• Ability to analyze code for maintainability, scalability, and security vulnerabilities.

General Questions that could be asked across experience levels:

1. Memory Management: How does the C standard library handle memory allocation? Discuss malloc, calloc, realloc, free, etc.
2. Concurrency: Explain the differences between processes and threads, and when you would use each.
3. IPC: Compare and contrast the different IPC mechanisms and their appropriate use cases.
4. Debugging: Describe tools and techniques for debugging memory leaks and race conditions in C programs.
5. Performance: Discuss strategies for profiling and optimizing C code performance.
6. Portability: Explain how you would write code that is portable across different platforms while using system-specific features when necessary.
7. Security: What are common security pitfalls in C programming, and how can they be mitigated?
8. Code Design: How do you approach designing a new module or feature in the C language? What patterns and practices do you follow?
9. Tooling: Discuss the role of static analysis tools in maintaining code quality and security.
10. Best Practices: What are best practices for writing maintainable, scalable, and secure C code?

These questions cover a wide range of topics that are critical for a system programmer working with the C language. The depth and complexity of the questions increase with experience, reflecting the candidate's growing expertise in system programming. It's also important to note that while the focus here is on C, understanding the underlying principles of the operating system, hardware, and compiler internals is crucial for a system programmer.