Function s_wait

* 获取进程是否存活状态 * @param pid 进程号 * @param exit_code_ptr 进程返回代码 * @param block 是否阻塞等待 * @return 进程是否还在运行 * Get the process's alive status. * @param pid Process ID * @param exit_code_ptr Process return code * @param block Whether to block and wait * @return Whether the process is still running * [AUTO-TRANSLATED:ef80ff17] */