Essential Topics Linux Server Developers Need to Ace Technical Interviews

The author, a senior developer in Shanghai, shares insights gathered from interviewing at more than 30 companies for Linux server development roles, aiming to help readers prepare for technical interviews.

1. Data Structures and Algorithms Focus

Many companies, especially Baidu and iQiyi, concentrate on data‑structure and algorithm skills. Typical questions include:

Quick sort : discuss steps, average/ best/ worst‑case complexities; description is sufficient for senior hiring.

Binary search : implement the algorithm or apply it to a concrete scenario such as computing a square root.

Linked list : delete a node, reverse a singly linked list, find intersection of two lists, requiring flawless code.

Implement basic functions : rewrite strcpy, memcpy, memmove, atoi with correct handling of edge cases and efficiency.

Additional data‑structure topics often appear:

Hash table : insertion algorithm, collision handling, generic element type.

AVL/B‑tree : concepts and details, e.g., MySQL index implementation.

Red‑black tree : definition, complexities, rotations, color changes; interviewers may probe STL map implementation.

2. Operating‑System and Networking Fundamentals

Companies such as Ele.me, Bilibili, and others blend algorithm questions with deeper system knowledge, covering OS principles, network protocols, and C++ specifics.

Core C++ topics frequently asked:

Purpose of virtual in inheritance, especially for destructors; order of constructor/destructor execution; layout of multiple inheritance.

Role of static, and usage scenarios for static_cast, reinterpret_cast, dynamic_cast.

Virtual table layout in diamond inheritance (e.g., class D inheriting B and C which both inherit A).

Interviewers also test knowledge of C++11 and Boost libraries, expecting familiarity with: auto, range‑based for, r‑value references and move constructors. std::forward, std::move.

New STL methods like emplace_back(), std::thread, std::chrono.

Smart pointers ( shared_ptr, unique_ptr, weak_ptr) and their implementation principles.

Thread‑synchronisation primitives ( std::mutex, std::condition_variable, std::lock_guard).

Lambda expressions, std::function, std::bind.

Network communication questions often probe TCP/IP stack details, socket API usage, and protocol nuances:

TCP state after a peer reboot without data exchange and how to clear it.

Congestion control mechanisms.

Common fields in TCP/IP headers.

Blocking vs non‑blocking socket behavior for send / recv.

Asynchronous connect implementation.

Usage of select and differences between select and epoll (level‑triggered vs edge‑triggered).

Socket options such as Nagle, keep‑alive, linger.

TCP vs UDP differences and appropriate scenarios.

Designing protocols to avoid packet “sticky‑packet” issues.

HTTP GET vs POST, sometimes requiring drawing the HTTP format.

Windows I/O completion ports (IOCP).

Operating‑system topics include ELF section layout, mapping to process address space, placement of global/static variables, protection vs real mode, interrupt vector tables, CAS operations, daemon creation, zombie processes, stack vs heap differences, calling conventions ( __cdecl, __stdcall, __thiscall, __fastcall), and synchronization primitives (mutexes, semaphores, condition variables, Windows events, critical sections). Process‑communication mechanisms such as shared memory, anonymous/named pipes, sockets, and message queues are also essential.

3. Project Experience

Interviewers often ask candidates to describe past projects that match the target role; senior or managerial positions may dig deeper into domain‑specific experience (e.g., game development, financial trading systems).

4. Unreliable Company Types

The author categorises problematic employers into four groups:

Pretentious “show‑off” firms : overly long interview processes, irrelevant high‑level questions, and low salary offers.

“Buddha” companies : friendly interviewers but no real hiring intent.

Bureaucratic “old‑lady‑wrapping‑cloth” firms : lengthy cycles, excessive document checks, and modest compensation.

Disrespectful firms : assign junior interviewers to senior candidates, ask trivial or irrelevant low‑level questions, and display unprofessional behavior.

5. Non‑Technical Considerations

Beyond technical skills, candidates should evaluate:

Whether the company supports long‑term technical growth versus short‑term salary gains.

Realistic salary expectations versus advertised ranges.

The value of interviewing at less‑desired companies for experience.

How well interviewers assess candidates (aim for at least 80% correct answers).

Clarity on future role responsibilities to avoid unwanted tasks.

Strategies for handling unknown questions (seek hints, discuss thought process).

Importance of solving written math/logic puzzles, as they reflect algorithmic thinking.

Maintaining confidence; each candidate’s experience is unique.

These reflections, distilled from interactions with 30+ companies, are intended to guide readers in preparing for and navigating technical interviews effectively.