VAX C Run-Time Library Reference Manual

This document is the VAX C Run-Time Library Reference Manual (Order Number: AI-JP84A-TE), published in March 1987 for VAX C Version 2.3.

Purpose and Audience: It serves as a comprehensive reference guide for both experienced and novice programmers, detailing the functions and macros available in the VAX C Run-Time Library (RTL). These functions cover a wide range of functionalities, including I/O operations, character and string manipulation, mathematical calculations, error detection, subprocess creation, system access, and screen management (Curses).

Key Content Areas: The manual is structured into twelve chapters and four appendices:

• RTL Information: Provides an overview of the VAX C RTL's implementation, including its use as a shareable image, macro handling, function/macro syntax, and specific details about I/O on VMS (RMS record and file formats, stream access). It also addresses portability concerns between UNIX and VMS systems.
• Functional Categories: Dedicated chapters describe Standard I/O, Terminal I/O, UNIX I/O, Character-Handling, String- and List-Handling, Math, Error-Handling, Memory Allocation, Subprocess, and System functions, as well as Curses Screen Management functions and macros.
• New Features (VAX C Version 2.3): Highlights new functions conforming to the System V Interface Definition and the Proposed ANSI C Language Standard, such as asctime, assert, bsearch, difftime, fmod, gmtime, memory manipulation functions (memchr, memcmp, memcpy, memmove, memset), qsort, setvbuf, string manipulation (strtod, strtol, strtoul, strtok), system calls, and formatted output functions (vprintf, vfprintf, vsprintf). Enhancements to existing functions like fopen/freopen (binary mode) and printf/scanf (new format flags) are also noted.
• Appendices: Offer a comparison of VAX C RTL functions/macros with other C implementations, lists of VAX C run-time modules and entry points, descriptions of VAX C definition modules, and a comprehensive syntax summary for all documented functions and macros.

The document emphasizes how VAX C functions interact with VMS Record Management Services (RMS) and VMS system services, and provides essential information for porting C programs between VMS and other operating systems.