Question

Which of the following system call is preferred over dup and dup2 for replicating file descriptor?

(a) dup3

(b) fcn

(c) fcntl

(d) exec

This question was posed to me in an interview for job.

I'm obligated to ask this question of Process Control System Calls topic in division System Programming II – Process Control & Unix System Performance of Unix

Answer 1

The correct option is (c) fcntl

To elaborate: POSIX calls dup and dup2 “redundant” functions and advocates the use of fcntl system call.