IBM jargon for user mode, the opposite of "supervisor state".
On IBM System 360, 370 and 390 mainframes privileged instructions may only be executed in "supervisor state". Application programs request the operating system to perform these operations by using the Supervisor Call (SVC) instruction.
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Nearby terms: probabilistic automaton « Probability of Failure on Demand « Probe « problem state » Problem Statement Language/Problem Statement Analyser » PROC » procedural