But of course, like any immutable system, there are mutable parts (otherwise, we couldn’t create any configuration files). OSTree handles this with “overlays” (actually, we use OverlayFS) that allow a read-write filesystem to be layered on top of the immutable system. For example, the /etc and /var directories are writable, while the rest of the system is read-only.
The segmentation unit performs two operations simultaneously: adding the segment base to produce the linear address and comparing the effective address against the segment limit. Both use dedicated 32-bit adder/subtractor circuits.
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（六）扰乱大型群众性活动秩序的其他行为。，详情可参考旺商聊官方下载
That honour went, of course, to Neil Armstrong and Buzz Aldrin.