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While screwing around and breaking things I came across these stupid commands (if executed in order it causes what I got):

cd / && cat vmlinuz

cd /boot/ && cat init*

It causes special characters that aren't recognized by the system like ��� however, for some reason it causes weird effects like causing iTerm2 to send a bell (a notification to the system) like the screen shot:

enter image description here

However, the weirdest this is that is causes Mac OSX to print (screenshot):

enter image description here

Can someone explain to my why this happens, especially over SSH?

Thanks in advance!

1 Answer 1

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Terminal.app probably implements the "media copy" (printer) escape sequence from VT100s. You can read about those control sequences at vt100.net, or in the XTerm Control Sequences, e.g.,

CSI Pm i  Media Copy (MC).
        Ps = 0  -> Print screen (default).
        Ps = 4  -> Turn off printer controller mode.
        Ps = 5  -> Turn on printer controller mode.
CSI ? Pm i
      Media Copy (MC, DEC-specific).
        Ps = 1  -> Print line containing cursor.
        Ps = 4  -> Turn off autoprint mode.
        Ps = 5  -> Turn on autoprint mode.
        Ps = 1  0  -> Print composed display, ignores DECPEX.
        Ps = 1  1  -> Print all pages.

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