privileged instruction[′priv·ə·lijd in′strək·shən]
A class of instructions, usually including storage protection setting, interrupt handling, timer control, input/output, and special processor status-setting instructions, that can be executed only when the computer is in a special privileged mode that is generally available to an operating or executive system, but not to user programs.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
A machine code instruction that may only be executed when the processor is running in supervisor mode. Privileged instructions include operations such as I/O and memory management.
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