GateQA — Free GATE CS Previous Year Questions & Mock Tests

GateQA is a free GATE CS preparation platform with 3,500+ previous-year questions (1987–2026), 36,000+ aptitude questions, full-length year-wise mock tests, a built-in GATE calculator, performance analytics, and full offline support.

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GateQA — Free GATE CS Preparation Platform

GateQA is a free GATE CS preparation platform featuring 3,500+ previous-year questions (1987–2026), 36,000+ aptitude questions, subject-wise and year-wise mock tests, performance analytics, and full offline support. Practice Operating Systems, Algorithms, DBMS, Computer Networks, Theory of Computation, Discrete Mathematics, Compiler Design, Digital Logic, and more.

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Operating System

GATE CSE 2021 Set 1 | Question: 14

Subject: Operating System
Paper: 2021 Set 1
Which of the following standard $C$ library functions will always invoke a system call when executed from a single-threaded process in a $\text{UNIX/Linux}$ operating system?
Answer: A, C

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