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Operating Systems · Quiz 1 · 15 Mar 2026 · January 2026 term

Question 6: Consider the following code snippet for the syscall funct…

Question 6

+3 marksOne correct option

Consider the following code snippet for the syscall function in kernel/syscall.c (RISC-V xv6):

Why does xv6 store the system call number in the

register before invoking the kernel?

  1. A

    To store the return value of the system call.

  2. B

    To indicate the number of bytes to be transferred.

  3. C

    To let the kernel identify which system call the user process is requesting.

  4. D

    To store the stack pointer for the child process.

Show answer

Correct answer

  • C

    To let the kernel identify which system call the user process is requesting.

See the whole paperTake it as a mock test

Question 6 of 18 in the IIT Madras BS Operating Systems (Operating Systems) Quiz 1 paper sat on 15 Mar 2026, in the January 2026 term. It carries 3 marks.

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