VAX/VMS System Services Reference Manual

This manual serves as a comprehensive reference for system and application programmers utilizing VAX/VMS system services, primarily with VAX-11 FORTRAN IV-PLUS and VAX-11 MACRO languages. It describes VAX/VMS system services as procedures for controlling resources, enabling inter-process communication, and performing core operating system functions like I/O coordination. The document outlines usage restrictions based on user privileges, process group associations, and access modes. It categorizes services into functional groups such as Event Flag, Asynchronous System Trap (AST), Logical Name, Input/Output, Process Control, Timer and Time Conversion, Condition Handling, Memory Management, and Change Mode services, providing coding conventions, examples, and detailed reference information for each.