HP OpenVMS systems documentation

HP C

Order Number: AA-RSMUC-TE

This manual describes the functions and macros in the HP C Run-Time Library for OpenVMS systems.

Revision/Update Information: This manual supersedes the HP C Run-Time Library Reference Manual for OpenVMS Systems, Order Number AA-RSMUB-TE, Version 7.3-2

Software Version: OpenVMS I64 Version 8.2
OpenVMS Alpha Version 8.2

Hewlett-Packard Company Palo Alto, California

© Copyright 2005 Hewlett-Packard Development Company, L.P.

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Portions of the HP C Run-Time Library have been implemented using source copyrighted by the University of California, Berkley and its contributors.

Copyright (c) 1981 Regents of the University of California.

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Contents

Index

This manual describes the HP C Run-Time Library (RTL) for the OpenVMS operating system on VAX, Alpha, and Intel Itanium processors. HP OpenVMS Industry Standard 64 for Integrity Servers is the full product name of the OpenVMS operating system on Intel Itanium processors. The shortened forms, OpenVMS I64 and I64, are also used throughout this manual.

This manual provides reference information about the C RTL functions and macros that perform input/output (I/O) operations, character and string manipulation, mathematical operations, error detection, subprocess creation, system access, screen management, and emulation of selected UNIX features. It also notes portability concerns between operating systems, where applicable.

The HP C RTL contains XPG4-compliant internationalization support, providing functions to help you develop software that can run in different languages and cultures.

The complete HP C Run-Time Library (C RTL) needed for use with the HP C and C++ compilers is distributed with the OpenVMS Alpha and I64 operating systems in both shared image and object module library form.

This manual no longer documents the socket routines used for writing Internet application programs for the TCP/IP Services protocol. For help on the socket routines, use the following:

$ HELP TCPIP_Services Programming_Interfaces Sockets_API

Also see the HP TCP/IP Services for OpenVMS product documentation.

Intended Audience

This manual is intended for experienced and novice programmers who need reference information on the functions and macros found in the HP C RTL.

Document Structure

This manual has the following chapters, reference section, and appendixes:

• Chapter 1 provides an overview of the HP C RTL.
• Chapter 2 discusses the Standard I/O, Terminal I/O, and UNIX I/O functions.
• Chapter 3 describes the character, string, and argument-list functions.
• Chapter 4 describes the error-handling and signal-handling functions.
• Chapter 5 explains the functions used to create subprocesses.
• Chapter 6 describes the Curses Screen Management functions.
• Chapter 7 discusses the math functions.
• Chapter 8 explains the memory allocation functions.
• Chapter 9 describes the functions used to interact with the operating system.
• Chapter 10 gives an introduction to the facilities provided in the HP C environment on OpenVMS systems for developing international software.
• Chapter 11 describes the date/time functions.
• The Reference Section describes all the functions in the HP C RTL.
• Appendix A contains version-dependency tables that list the HP C RTL functions supported on different OpenVMS versions.
• Appendix B lists the function prototypes that are duplicated in more than one header file.

Related Documents

The following documents may be useful when programming in HP C for OpenVMS Systems:

• HP C User's Guide for OpenVMS Systems---For C programmers who need information on using HP C for OpenVMS Systems.
• HP C Language Reference Manual---Provides language reference information for HP C on HP systems.
• VAX C to HP C Migration Guide---To help OpenVMS VAX application programmers migrate from VAX C to HP C.
• HP C Installation Guide for OpenVMS VAX Systems---For OpenVMS system programmers who install the HP C software on VAX systems.
• HP C Installation Guide for OpenVMS Alpha Systems---For OpenVMS system programmers who install the HP C software on Alpha systems.
• OpenVMS Master Index---For programmers who need to work with the VAX and Alpha machine architectures or the OpenVMS system services. This index lists manuals that cover the individual topics concerning access to the OpenVMS operating system.
• HP TCP/IP Services for OpenVMS Sockets API and System Services Programming---For information on the socket routines used for writing Internet application programs for the HP TCP/IP Services for OpenVMS product or other implementations of the TCP/IP protocol.
• HP TCP/IP Services for OpenVMS Guide to IPv6---For information on HP TCP/IP Services for OpenVMS IPv6 features, how to install and configure IPv6 on your system, changes in the socket application programming interface (API), and how to port your applications to run in an IPv6 environment.
• X/Open Portability Guide, Issue 3---Documents what is commonly known as the XPG3 specification.
• X/Open CAE Specification System Interfaces and Headers, Issue 4---Documents what is commonly known as the XPG4 specification.
• X/Open CAE Specification, System Interfaces and Headers, Issue 4, Version 2---Documents what is commonly known as XPG4 V2.
• X/Open CAE Specification, System Interfaces and Headers, Issue 5---Documents what is commonly known as the XPG5 specification.
• Technical Standard. System Interfaces, Issue 6---Combined Open Group Technical Standard and IEEE standard. IEEE Std 1003.1-2001, sometimes known as XPG6.
• Standard for Information Technology - Portable Operating System Interface (POSIX) - Part 1: System Application Program Interface (API)---Amendment 2: Threads Extension [C Language]---Documents what is also known as POSIX 1003.1c-1995.
• ISO/IEC 9945-2:1993 - Information Technology - Portable Operating System Interface (POSIX) - Part 2: Shell and Utilities---Documents what is also known as ISO POSIX-2.
• ISO/IEC 9945-1:1990 - Information Technology - Portable Operating System Interface (POSIX) - Part 1: System Application Programming Interface (API) (C Language)---Documents what is also known as ISO POSIX-1.
• ANSI/ISO/IEC 9899:1999 - Programming Languages - C---The C99 standard, published by ISO in December, 1999 and adopted as an ANSI standard in April, 2000.
• ISO/IEC 9899:1990-1994 - Programming Languages - C, Amendment 1: Integrity---Documents what is also known as ISO C, Amendment 1.
• ISO/IEC 9899:1990[1992] - Programming Languages - C---Documents what is also known as ISO C. The normative part is the same as X3.159-1989, American National Standard for Information Systems - Programming Language C, also known as ANSI C.

For more information about HP OpenVMS products and services, access the HP Web site at the following location:

http://www.hp.com/go/openvms

Reader's Comments

HP welcomes your comments on this manual. Please send comments to either of the following addresses:

Internet	openvmsdoc@hp.com
Postal Mail	Hewlett-Packard Company OSSG Documentation Group, ZKO3-4/U08 110 Spit Brook Rd. Nashua, NH 03062-2698

How to Order Additional Documentation

For information about how to order additional documentation, visit the following Web site address:

http://www.hp.com/go/openvms/doc/order

Conventions Used in this Document

Platform Labels

A platform is a combination of operating system and hardware that provides a distinct environment. This manual contains information applicable to the OpenVMS operating system running on VAX, Alpha, and Itanium processors.

The information in this manual applies to all of these processors, except when specifically labeled as follows:

Label	Explanation
(ALPHA ONLY)	Specific to an Alpha processor.
(I64 ONLY)	Specific to an Intel Itanium processor running the OpenVMS operating system. On this platform, the product name of the operating system is OpenVMS Industry Standard 64 (or its abbreviated forms, OpenVMS I64 or I64).
(VAX ONLY)	Specific to a VAX processor.
(ALPHA, I64)	Specific to I64 and Alpha processors.

New and Changed Features - OpenVMS Version 8.2

The following enhancements have been made to the C Run-Time Library for OpenVMS Version 8.2. These enhancements provide improved UNIX portability, standards compliance, and the flexibility of additional user-controlled feature selections. New C RTL functions are also included.

• I64 support
  The HP C RTL is now supported on HP OpenVMS Industry Standard 64 for Integrity Servers as well as on Alpha and VAX systems.
• File-locking functions
  The following X/Open file-pointer-locking functions have been added in support of UNIX portability. They allow a user to lock file pointers and provide access synchronization across threaded programs:

  flockfile ftrylockfile funlockfile clearerr_unlocked getc_unlocked getchar_unlocked feof_unlocked ferror_unlocked fgetc_unlocked fputc_unlocked putc_unlocked putchar_unlocked

• Standard-compliant stat structure
  In support of UNIX portability, a new standard-compliant definition of the stat structure and associated definitions have been added to <stat.h> . To use these new definitions, applications must compile with a new feature macro defined:
  _USE_STD_STAT
• File-system statistics support
  The following X/Open functions have been added in support of UNIX portability:

  statvfs fstatvfs

• fcntl file status flags
  The F_SETFL and F_GETFL command options have been added to the fcntl function to set and get file status flags.
• glob and globfree 64-bit support
  64bit support is added for the glob and globfree functions. As a result, the following additional function entry points are now available for use with 32-bit and 64-bit pointer sizes:

  _glob32 _glob64 _globfree32 _globfree64

• socketpair socket routine
  The socketpair socket routine has been added. This routine is used for creating a pair of connected sockets and requires the underlying TCP/IP product to have the TCPIP$SOCKETPAIR function available.