Privileged Operations

Summary

This document serves as a technical manual for managing and performing "privileged operations" within the ETOS operating system. It details the mechanisms by which system managers and privileged users can control system behavior, hardware access, and maintenance tasks.

Key areas covered include:

• Privileged Commands: Explains the use of the PRIV command to grant user privileges, adjust system priority levels, and control CPU quantum lengths.
• Memory Management: Details PEEK and POKE commands for physical memory access, and LOCK/UNLOCK/HOOK system calls for managing memory resident tasks and interrupt handling.
• System Maintenance: Provides instructions for the BROADCAST, FORCE, and SHUTUP commands, as well as procedures for mounting/dismounting disks and managing device handlers.
• Device Handling: Outlines the specific requirements for accessing privileged hardware such as DECtape drives, floppy disks, and high-speed paper tape reader/punches, emphasizing that these operations require privileged status due to their potential impact on system stability and data integrity.
• System Automation: Describes how to set up automatic login batches and system initializations using the INIT.CM file and configuration utilities to automate system startup and maintenance.
• Statistics and Monitoring: Explains the use of the USAGE program to track and initialize job statistics for accounts, and the SPOOLR program for line printer and terminal output management.
• Real-Time Programming (Chapter 7 introduction): Briefly introduces concepts for real-time task management within ETOS, including interrupt handling and system structure, with sample programs for practical implementation.

The document warns that many of these operations are potentially dangerous to system stability and should be restricted to qualified personnel.