You can use waitpid() in Linux if you want to just wait infinitely for the process to die.

在 Linux 中，如果您希望无限期等待进程被杀死，则可以使用 waitpid()。

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ECHILD -- The wait() or waitpid() function tried to wait for a child process to exit, but all children have already exited.

ECHILD：wait() 或 waitpid() 函数尝试等待退出子进程，但所有子项都已经退出。

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In this code: pid_t waitpid(pid_t pid, int *status, int options), waitpid() infinitely waits for the child process to terminate.

在这段代码中：pid_t waitpid(pid_t pid, int *status, int options)，waitpid() 会无限期等待子进程的终止。

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