The explanation of Figure 2-3 says this.
Originally Posted by Chapter 2: Process Management and Scheduling(P48)
Each of them therefore has its own init task with PID 0, and the PIDs of other tasks are assigned in increasing order. Both child namespaces have an init task
with PID 0, and two processes with PIDs 2 and 3, respectively.
But, although the explanation says that there is a task with PID 0, Figure 2-3 doesn't show a PID 0, but shows a task with PID 1 instead.
Why is that? Someone please clarify.
Thanks in advance.