Interview Q&A / Operating Systems
Operating Systems interview questions
Processes, threads, scheduling, memory and deadlocks, in plain words.
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- If a program calls fork() three times in a row, how many processes run in total?
Each unconditional fork() doubles the number of processes, so n sequential calls give 2^n processes in total: 8 for three calls, meaning 7 new children plus the original.
IntermediateQuick answer1 min read - What is the difference between fork() and exec()?
fork() creates a new process that is a copy of the caller. exec() replaces the current process's program with a new one, keeping the same PID. Shells combine them: fork a child, then exec the command in it.
IntermediateQuick answer1 min read