VSI Openvms C Language Reference Manual

Total Page:16

File Type:pdf, Size:1020Kb

VSI Openvms C Language Reference Manual VSI OpenVMS C Language Reference Manual Document Number: DO-VIBHAA-008 Publication Date: May 2020 This document is the language reference manual for the VSI C language. Revision Update Information: This is a new manual. Operating System and Version: VSI OpenVMS I64 Version 8.4-1H1 VSI OpenVMS Alpha Version 8.4-2L1 Software Version: VSI C Version 7.4-1 for OpenVMS VMS Software, Inc., (VSI) Bolton, Massachusetts, USA C Language Reference Manual Copyright © 2020 VMS Software, Inc. (VSI), Bolton, Massachusetts, USA Legal Notice Confidential computer software. Valid license from VSI required for possession, use or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license. The information contained herein is subject to change without notice. The only warranties for VSI products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. VSI shall not be liable for technical or editorial errors or omissions contained herein. HPE, HPE Integrity, HPE Alpha, and HPE Proliant are trademarks or registered trademarks of Hewlett Packard Enterprise. Intel, Itanium and IA64 are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries. Java, the coffee cup logo, and all Java based marks are trademarks or registered trademarks of Oracle Corporation in the United States or other countries. Kerberos is a trademark of the Massachusetts Institute of Technology. Microsoft, Windows, Windows-NT and Microsoft XP are U.S. registered trademarks of Microsoft Corporation. Microsoft Vista is either a registered trademark or trademark of Microsoft Corporation in the United States and/or other countries. Motif is a registered trademark of The Open Group UNIX is a registered trademark of The Open Group. The VSI OpenVMS documentation set is available on CD. ii C Language Reference Manual Preface .................................................................................................................................... xi 1. Intended Audience ......................................................................................................... xi 2. Purpose of the ANSI Standard ........................................................................................ xi 3. Manual Structure .......................................................................................................... xii 4. Associated Documents .................................................................................................. xii 5. VSI Encourages Your Comments .................................................................................. xiii 6. How to Order Additional Documentation ...................................................................... xiii 7. Typographical Conventions .......................................................................................... xiii Chapter 1. Lexicon ................................................................................................................ 1 1.1. Character Set ............................................................................................................... 2 1.1.1. Trigraph Sequences ........................................................................................... 4 1.1.2. Digraph Sequences ............................................................................................ 4 1.2. Identifiers .................................................................................................................... 5 1.3. Universal Character Names .......................................................................................... 6 1.4. Comments .................................................................................................................... 6 1.5. Keywords .................................................................................................................... 7 1.6. Operators ..................................................................................................................... 8 1.7. Punctuators .................................................................................................................. 9 1.8. String Literals ............................................................................................................ 10 1.9. Constants ................................................................................................................... 11 1.9.1. Integer Constants ............................................................................................. 11 1.9.2. Floating-Point Constants .................................................................................. 13 1.9.2.1. Semantics ............................................................................................. 13 1.9.2.2. Floating-Point Type ............................................................................... 14 1.9.2.3. Hexadecimal Floating-Point Constants ................................................... 14 1.9.2.4. Examples .............................................................................................. 14 1.9.3. Character Constants ......................................................................................... 15 1.9.3.1. Wide Characters .................................................................................... 15 1.9.3.2. Multibyte Characters ............................................................................. 16 1.9.3.3. Character Escape Sequences .................................................................. 16 1.9.3.4. Numeric Escape Sequences ................................................................... 17 1.9.4. Enumeration Constants .................................................................................... 18 1.10. Header Files ............................................................................................................. 18 1.11. Limits ...................................................................................................................... 18 1.11.1. Translation Limits .......................................................................................... 19 1.11.2. Numerical Limits ........................................................................................... 19 1.11.3. Character Display .......................................................................................... 20 Chapter 2. Basic Concepts .................................................................................................. 21 2.1. Blocks ....................................................................................................................... 22 2.2. Compilation Units ...................................................................................................... 22 2.3. Scope ......................................................................................................................... 23 2.3.1. File Scope ....................................................................................................... 23 2.3.2. Block Scope .................................................................................................... 24 2.3.3. Function Scope ................................................................................................ 24 2.3.4. Function Prototype Scope ................................................................................ 24 2.4. Visibility .................................................................................................................... 24 2.5. Side Effects and Sequence Points ................................................................................ 25 2.6. Incomplete Type ......................................................................................................... 26 2.7. Compatible and Composite Types ............................................................................... 27 2.8. Linkage ...................................................................................................................... 29 2.9. Tentative Definitions .................................................................................................. 30 iii C Language Reference Manual 2.10. Storage Classes ........................................................................................................ 30 2.10.1. The auto Class ............................................................................................... 31 2.10.2. The register Class .......................................................................................... 31 2.10.3. The static Class ............................................................................................. 32 2.10.4. The extern Class ............................................................................................ 32 2.11. Storage-Class Modifiers ............................................................................................ 32 2.11.1. The __inline Modifier .................................................................................... 33 2.11.2. The inline Modifier ........................................................................................ 33 2.11.2.1. Example – Using the inline Function Specifier ...................................... 34
Recommended publications
  • Preview Objective-C Tutorial (PDF Version)
    Objective-C Objective-C About the Tutorial Objective-C is a general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. This is the main programming language used by Apple for the OS X and iOS operating systems and their respective APIs, Cocoa and Cocoa Touch. This reference will take you through simple and practical approach while learning Objective-C Programming language. Audience This reference has been prepared for the beginners to help them understand basic to advanced concepts related to Objective-C Programming languages. Prerequisites Before you start doing practice with various types of examples given in this reference, I'm making an assumption that you are already aware about what is a computer program, and what is a computer programming language? Copyright & Disclaimer © Copyright 2015 by Tutorials Point (I) Pvt. Ltd. All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. The user of this e-book can retain a copy for future reference but commercial use of this data is not allowed. Distribution or republishing any content or a part of the content of this e-book in any manner is also not allowed without written consent of the publisher. We strive to update the contents of our website and tutorials as timely and as precisely as possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our website or its contents including this tutorial. If you discover any errors on our website or in this tutorial, please notify us at [email protected] ii Objective-C Table of Contents About the Tutorial ..................................................................................................................................
    [Show full text]
  • Strings in C++
    Programming Abstractions C S 1 0 6 X Cynthia Lee Today’s Topics Introducing C++ from the Java Programmer’s Perspective . Absolute value example, continued › C++ strings and streams ADTs: Abstract Data Types . Introduction: What are ADTs? . Queen safety example › Grid data structure › Passing objects by reference • const reference parameters › Loop over “neighbors” in a grid Strings in C++ STRING LITERAL VS STRING CLASS CONCATENATION STRING CLASS METHODS 4 Using cout and strings int main(){ int n = absoluteValue(-5); string s = "|-5|"; s += " = "; • This prints |-5| = 5 cout << s << n << endl; • The + operator return 0; concatenates strings, } and += works in the way int absoluteValue(int n) { you’d expect. if (n<0){ n = -n; } return n; } 5 Using cout and strings int main(){ int n = absoluteValue(-5); But SURPRISE!…this one string s = "|-5|" + " = "; doesn’t work. cout << s << n << endl; return 0; } int absoluteValue(int n) { if (n<0){ n = -n; } return n; } C++ string objects and string literals . In this class, we will interact with two types of strings: › String literals are just hard-coded string values: • "hello!" "1234" "#nailedit" • They have no methods that do things for us • Think of them like integer literals: you can’t do "4.add(5);" //no › String objects are objects with lots of helpful methods and operators: • string s; • string piece = s.substr(0,3); • s.append(t); //or, equivalently: s+= t; String object member functions (3.2) Member function name Description s.append(str) add text to the end of a string s.compare(str) return
    [Show full text]
  • Balanced Ternary Arithmetic on the Abacus
    Balanced Ternary Arithmetic on the Abacus What is balanced ternary? It is a ternary number system where the digits of a number are powers of three rather than powers of ten, but instead of adding multiples of one or two times various powers of three to make up the desired number, in balanced ternary some powers of three are added and others are subtracted. Each power of three comprisising the number is represented by either a +, a -, or 0, to show that the power of three is either added, subtracted, or not present in the number. There are no multiples of a power of three greater than +1 or -1, which greatly simplifies multiplication and division. Another advantage of balanced ternary is that all integers can be represented, both positive and negative, without the need for a separate symbol to indicate plus or minus. The most significant ternary digit (trit) of any positive balanced ternary number is + and the most significant trit of any negative number is -. Here is a list of a few numbers in decimal, ternary, and balanced ternary: Decimal Ternary Balanced ternary ------------------------------------------------- -6 - 20 - + 0 (-9+3) -5 - 12 - + + (-9+3+1) -4 - 11 - - ( -3-1) -3 - 10 - 0 etc. -2 - 2 - + -1 - 1 - 0 0 0 1 1 + 2 2 + - 3 10 + 0 4 11 + + 5 12 + - - 6 20 + - 0 Notice that the negative of a balanced ternary number is formed simply by inverting all the + and - signs in the number. Thomas Fowler in England, about 1840, built a balanced ternary calculating machine capable of multiplying and dividing balanced ternary numbers.
    [Show full text]
  • Using ANSI Color Codes General Configuration of the Shell
    LinuxFocus article number 335 http://linuxfocus.org Colorful Shells -- Using ANSI Color Codes by Nico Golde <nico/at/ngolde.de> About the author: At present Nico is still a Abstract: student. Since a few years he keeps very busy with In an ANSI compatible terminal (like xterm, rxvt, konsole ...) text may Linux, he also takes part in be shown in colors different from black/white. This article will a number of Open Source demonstrate text in bold or in color. Projects. _________________ _________________ _________________ Translated to English by: Jürgen Pohl <sept.sapins(at)verizon.net> General In real life every Linux user gets to face the Bash. At first glance that looks very boring, but there are many possibilities to give one’s shell the personal touch. Colored enhancement of the shell prompt make the shell unique as well as better legible. In my description I will refer to the Bash shell. The escape sequences may differ between terminals, for this text I am using an ANSI terminal. Configuration of the Shell Setting of shell colors happens in the personal configuration file of the bash ~/.bashrc or in the global configuration file /etc/bashrc. The appearance of the prompt is being set with the PS1 variable in bashrc. Generally, the entry should look like this: ~/.bashrc: PS1="\s-\v\$ " \s stands for the name of the shell and -\v for its version. At the end of the prompt we are placing a $. Since this gets a bit boring, the following entry - which is default in most Linux distributions - may be used: ~/.bashrc: PS1="\u@\h \w \$ " This stands for user@ current_directory $, which is the normal shell prompt most Linux users are familiar with.
    [Show full text]
  • CS 106 Introduction to Computer Science I
    CS 106 Introduction to Computer Science I 07 / 06 / 2021 Instructor: Michael Eckmann Today’s Topics • Introduction • Review the syllabus – including the policies on academic dishonesty and improper collaboration • Introductory comments on programming languages • An example of a simple Python program • Printing Michael Eckmann - Skidmore College - CS 106 - Summer 2021 Who is your instructor? • I'm Mike Eckmann, an Associate Professor in the Computer Science Dept., Skidmore College. I have been at Skidmore since 2004. Before coming to Skidmore I was at Lehigh University in PA. • I studied Mathematics and Computer Engineering and Computer Science all at Lehigh University. • I was employed as a programmer (systems analyst) for eight years. Michael Eckmann - Skidmore College - CS 106 - Summer 2021 1st Homework • Read the syllabus and review the improper collaboration policy (both will be available on our course webpage.) • Read chapter 1 of text. • Will send course webpage and a questionnaire via email later this class. Michael Eckmann - Skidmore College - CS 106 - Summer 2021 Syllabus • Office hours • Collaboration policy – By appointment • Grading scheme • Text book • Workload • Assignments • Student preparation – Programs & HW before class Note: The most up-to-date syllabus will be found on the course web page. Michael Eckmann - Skidmore College - CS 106 - Summer 2021 This semester we will ... • Be introduced to computer science. • Learn programming (in Python)! • Solve problems and learn to think like programmers. • Hopefully have a fun learning experience. Michael Eckmann - Skidmore College - CS 106 - Summer 2021 Computer Science is ... • more than computer programming. Michael Eckmann - Skidmore College - CS 106 - Summer 2021 Programming Languages • Machine • Assembly • High-level – in no particular order – Pascal, C, C++, Basic, Fortran, Java, Python and many, many more ..
    [Show full text]
  • Variable Feature Usage Patterns in PHP
    Variable Feature Usage Patterns in PHP Mark Hills East Carolina University, Greenville, NC, USA [email protected] Abstract—PHP allows the names of variables, classes, func- and classes at runtime. Below, we refer to these generally as tions, methods, and properties to be given dynamically, as variable features, and specifically as, e.g., variable functions expressions that, when evaluated, return an identifier as a string. or variable methods. While this provides greater flexibility for programmers, it also makes PHP programs harder to precisely analyze and understand. The main contributions presented in this paper are as follows. In this paper we present a number of patterns designed to First, taking advantage of our prior work, we have developed recognize idiomatic uses of these features that can be statically a number of patterns for detecting idiomatic uses of variable resolved to a precise set of possible names. We then evaluate these features in PHP programs and for resolving these uses to a patterns across a corpus of 20 open-source systems totaling more set of possible names. Written using the Rascal programming than 3.7 million lines of PHP, showing how often these patterns occur in actual PHP code, demonstrating their effectiveness at language [2], [3], these patterns work over the ASTs of the statically determining the names that can be used at runtime, PHP scripts, with more advanced patterns also taking advantage and exploring anti-patterns that indicate when the identifier of control flow graphs and lightweight analysis algorithms for computation is truly dynamic. detecting value flow and reachability. Each of these patterns works generally across all variable features, instead of being I.
    [Show full text]
  • AVR244 AVR UART As ANSI Terminal Interface
    AVR244: AVR UART as ANSI Terminal Interface Features 8-bit • Make use of standard terminal software as user interface to your application. • Enables use of a PC keyboard as input and ascii graphic to display status and control Microcontroller information. • Drivers for ANSI/VT100 Terminal Control included. • Interactive menu interface included. Application Note Introduction This application note describes some basic routines to interface the AVR to a terminal window using the UART (hardware or software). The routines use a subset of the ANSI Color Standard to position the cursor and choose text modes and colors. Rou- tines for simple menu handling are also implemented. The routines can be used to implement a human interface through an ordinary termi- nal window, using interactive menus and selections. This is particularly useful for debugging and diagnostics purposes. The routines can be used as a basic interface for implementing more complex terminal user interfaces. To better understand the code, an introduction to ‘escape sequences’ is given below. Escape Sequences The special terminal functions mentioned (e.g. text modes and colors) are selected using ANSI escape sequences. The AVR sends these sequences to the connected terminal, which in turn executes the associated commands. The escape sequences are strings of bytes starting with an escape character (ASCII code 27) followed by a left bracket ('['). The rest of the string decides the specific operation. For instance, the command '1m' selects bold text, and the full escape sequence thus becomes 'ESC[1m'. There must be no spaces between the characters, and the com- mands are case sensitive. The various operations used in this application note are described below.
    [Show full text]
  • Strings String Literals String Variables Warning!
    Strings String literals • Strings are not a built-in data type. char *name = "csc209h"; printf("This is a string literal\n"); • C provides almost no special means of defining or working with strings. • String literals are stored as character arrays, but • A string is an array of characters you can't change them. terminated with a “null character” ('\0') name[1] = 'c'; /* Error */ • The compiler reserves space for the number of characters in the string plus one to store the null character. 1 2 String Variables Warning! • arrays are used to store strings • Big difference between a string's length • strings are terminated by the null character ('\0') and size! (That's how we know a string's length.) – length is the number of non-null characters • Initializing strings: currently present in the string – char course[8] = "csc209h"; – size if the amount of memory allocated for – char course[8] = {'c','s','c',… – course is an array of characters storing the string – char *s = "csc209h"; • Eg., char s[10] = "abc"; – s is a pointer to a string literal – length of s = 3, size of s = 10 – ensure length+1 ≤ size! 3 4 String functions Copying a string • The library provides a bunch of string char *strncpy(char *dest, functions which you should use (most of the char *src, int size) time). – copy up to size bytes of the string pointed to by src in to dest. Returns a pointer to dest. $ man string – Do not use strcpy (buffer overflow problem!) • int strlen(char *str) – returns the length of the string. Remember that char str1[3]; the storage needed for a string is one plus its char str2[5] = "abcd"; length /*common error*/ strncpy(str1, str2, strlen(str2));/*wrong*/ 5 6 Concatenating strings Comparing strings char *strncat(char *s1, const char *s2, size_t n); int strcmp(const char *s1, const char *s2) – appends the contents of string s2 to the end of s1, and returns s1.
    [Show full text]
  • Introduction to C++
    GVNS I PUC Computer Science Notes Chapter 7 – INTRODUCTION TO C++ UNIT C – Chapter 7 – INTRODUCTION TO C++ BLUEPRINT 1 MARK 2 MARK 3 MARK 5 MARK TOTAL 1 0 1 1 9 ONE Mark Questions and Answers 1. Who developed “ C++ “ programming language and where? Bjarne Stroustrup designed C++ programming language at AT & T Bell Labs. 2. C++ is a subset of C. True or false? True 3. How can comments be included in a program? Comments can be included in C++ program by writing the comment between the symbols /* and */ or by starting the comment with double front slash ( // ). 4. Define token. A token is the smallest individual unit in a program. 5. Mention two tokens. Two tokens are keyword, identifier. (Note: refer to your textbook for more tokens) 6. What are keywords? Keywords are predefined word with some meanings. 7. Mention any four keywords in C++. The four keywords are int, if, do, for. (Note: refer to your textbook for more keywords) 8. What is a constant? Constants are quantities whose value cannot be changed during the execution of a program. 9. What are escape sequences? Escape sequences are characters that as special meaning and it starts with back slash ( \ ). 10. Mention any two escape sequences. Two escape sequences are \n and \t (Note: refer to your textbook for more escape sequences) 11. What is a string? String is a sequence of characters enclosed in double quotes. 12. What are punctuators? Punctuators are symbols used in a C++ program as seperators. 13. What is an operand? The data items on which operators act are called operands.
    [Show full text]
  • POSTLUDE P.1 Letter Frequencies
    POSTLUDE A Prelude opened this textbook with the puzzle Mastermind that introduced combinatorial reasoning in a recreational setting. This Postlude looks at a cryptanalysis problem that is again of a recreational nature but also illustrates the less structured side of combinatorial reasoning as it often occurs in real-world problems. In particular, we will look at a simple cryptographic scheme in which the analysis of underlying combinatorial problems is complicated by the somewhat random pattern of letters in English text. P.1 Letter Frequencies There have been many tables produced of the relative frequencies of letters in English writing, starting with Samuel Morse (of Morse code fame). We use frequencies averaged over several tables. Most Common Letters in English Text Vowels Consonants E 12% T 9% A, I, O 8 % N, R, S 6-8% D, L 4% The least frequent letters, all consonants, are: J, Q, X, Z below .05% As we shall see, it is also useful to know which pairs of consecutive letters, called digraphs, are most frequent. The eight most common digraphs are Most frequent: TH Second most frequent: HE Next six most frequent: ER, RE and AN, EN, IN, ON N is unique among the very frequent letters in that close to 90% of its occurrences are preceded by a vowel; other frequent letters have a much wider range of other letters preceding them. Some other frequent digraphs that can be helpful are: ES, SE ED, DE ST TE, TI, TO OF Frequent consonants tend to appear beside vowels but vowels do not occur side-by-side often and similarly frequent consonants do not appear side-by-side often except for TH and ST.
    [Show full text]
  • ANSI® Programmer's Reference Manual Line Matrix Series Printers
    ANSI® Programmer’s Reference Manual Line Matrix Series Printers Printronix, LLC makes no representations or warranties of any kind regarding this material, including, but not limited to, implied warranties of merchantability and fitness for a particular purpose. Printronix, LLC shall not be held responsible for errors contained herein or any omissions from this material or for any damages, whether direct, indirect, incidental or consequential, in connection with the furnishing, distribution, performance or use of this material. The information in this manual is subject to change without notice. This document contains proprietary information protected by copyright. No part of this document may be reproduced, copied, translated or incorporated in any other material in any form or by any means, whether manual, graphic, electronic, mechanical or otherwise, without the prior written consent of Printronix, LLC Copyright © 1998, 2012 Printronix, LLC All rights reserved. Trademark Acknowledgements ANSI is a registered trademark of American National Standards Institute, Inc. Centronics is a registered trademark of Genicom Corporation. Dataproducts is a registered trademark of Dataproducts Corporation. Epson is a registered trademark of Seiko Epson Corporation. IBM and Proprinter are registered trademarks and PC-DOS is a trademark of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation. Printronix, IGP, PGL, LinePrinter Plus, and PSA are registered trademarks of Printronix, LLC. QMS is a registered
    [Show full text]
  • Strings String Literals Continuing a String Literal Operations on String
    3/4/14 String Literals • A string literal is a sequence of characters enclosed within double quotes: "When you come to a fork in the road, take it." Strings • String literals may contain escape sequences. • Character escapes often appear in printf and scanf format strings. Based on slides from K. N. King and Dianna Xu • For example, each \n character in the string "Candy\nIs dandy\nBut liquor\nIs quicker.\n --Ogden Nash\n" causes the cursor to advance to the next line: Bryn Mawr College Candy CS246 Programming Paradigm Is dandy But liquor Is quicker. --Ogden Nash Continuing a String Literal How String Literals Are Stored • The backslash character (\) • The string literal "abc" is stored as an array of printf("When you come to a fork in the road, take it. \ four characters: --Yogi Berra"); Null o In general, the \ character can be used to join two or character more lines of a program into a single line. • When two or more string literals are adjacent, the compiler will join them into a single string. • The string "" is stored as a single null character: printf("When you come to a fork in the road, take it. " "--Yogi Berra"); This rule allows us to split a string literal over two or more lines How String Literals Are Stored Operations on String Literals • Since a string literal is stored as an array, the • We can use a string literal wherever C allows a compiler treats it as a pointer of type char *. char * pointer: • Both printf and scanf expect a value of type char *p; char * as their first argument.
    [Show full text]