OpenVMS System Services Reference Manual

This document, published in December 1995, is the first part of a two-part reference manual for OpenVMS System Services, covering services from A through $GETMSG. It details routines used by the OpenVMS operating system for resource control, inter-process communication, I/O control, and other system functions. The manual explicitly addresses support for OpenVMS Alpha's 64-bit virtual memory addressing, including terminology for 32-bit and 64-bit friendly/system services, and explains how 64-bit addressing affects system services. It supersedes previous versions for OpenVMS AXP and VAX Version 6.1, and applies to OpenVMS Alpha Version 7.0 and OpenVMS VAX Version 7.0.