imagine the following situation: the existing process Agraine fork generates child process B, and child process B calls exit (0), then B sends a SIGCHLD signal to parent process A, and parent process A chooses to ignore this signal, and process B becomes a dead process.
so what happens if An ends normally at this point, and B should be handed over to become a child of the init process? Will B resend the SIGCHLD signal to init? If not, how will B end in the end?
B will not send any more signals, and this zombie process will eventually be automatically recycled by the init process (pid=1).
Please refer to
When a process loses its parent, init becomes its new parent. Init periodically executes the wait system call to reap any zombies with init as parent.
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