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control-S: vi.

Stop talking for a second.” From the ASCII DC3 or XOFF character (the pronunciation /X-of/ is therefore also used). Control-S differs from control-O in that the person is asked to stop talking (perhaps because you are on the phone) but will be allowed to continue when you're ready to listen to him — as opposed to control-O, which has more of the meaning of “Shut up.” Considered silly.