Question

In 2018, a very simple Linux utility that performs this action was found to have a race condition leading to privilege escalation, leading to the creation of a satirical website dubbing the vulnerability “Holey [this action]”. On older PCs, this action is performed by setting Channel 2 of the Intel 8253 PIT chip. Many early computers, including the Apple II, have text written on the “G” key that indicates this action is triggered by pressing control-G. During a firmware process called POST, namesake “codes” are specified by the frequency and (*) spacing of this action. This action can happen when printing the character with ASCII (“ASS-kee”) value (10[1])7, which is represented by the escape sequence “backslash (10[1])a”. This action happens when printing the control character abbreviated B-E-L, which was originally used to signal teleprinters. For 10 points, computers might perform what physical action to notify users of errors or other alerts? ■END■ (10[2])

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