• Complain

Dougherty Dale - Sed & Awk

Here you can read online Dougherty Dale - Sed & Awk full text of the book (entire story) in english for free. Download pdf and epub, get meaning, cover and reviews about this ebook. City: Cambridge, LaVergne, year: 1997, publisher: Ingram Publisher Services distributor, OReilly Media, Inc, genre: Computer. Description of the work, (preface) as well as reviews are available. Best literature library LitArk.com created for fans of good reading and offers a wide selection of genres:

Romance novel Science fiction Adventure Detective Science History Home and family Prose Art Politics Computer Non-fiction Religion Business Children Humor

Choose a favorite category and find really read worthwhile books. Enjoy immersion in the world of imagination, feel the emotions of the characters or learn something new for yourself, make an fascinating discovery.

Dougherty Dale Sed & Awk

Sed & Awk: summary, description and annotation

We offer to read an annotation, description, summary or preface (depends on what the author of the book "Sed & Awk" wrote himself). If you haven't found the necessary information about the book — write in the comments, we will try to find it.

Annotation

sed & awk describes two text processing programs that are mainstays of the UNIX programmers toolbox.

sed is a stream editor for editing streams of text that might be too large to edit as a single file, or that might be generated on the fly as part of a larger data processing step. The most common operation done with sed is substitution, replacing one block of text with another.

awk is a complete programming language. Unlike many conventional languages, awk is data driven -- you specify what kind of data you are interested in and the operations to be performed when that data is found. awk does many things for you, including automatically opening and closing data files, reading records, breaking the records up into fields, and counting the records. While awk provides the features of most conventional programming languages, it also includes some unconventional features, such as extended regular expression matching and associative arrays. sed & awk describes both programs in detail and includes a chapter of example sed and awk scripts.

This edition covers features of sed and awk that are mandated by the POSIX standard. This most notably affects awk, where POSIX standardized a new variable, CONVFMT, and new functions, toupper() and tolower(). The CONVFMT variable specifies the conversion format to use when converting numbers to strings (awk used to use OFMT for this purpose). The toupper() and tolower() functions each take a (presumably mixed case) string argument and return a new version of the string with all letters translated to the corresponding case.

In addition, this edition covers GNU sed, newly available since the first edition. It also updates the first edition coverage of Bell Labs nawk and GNU awk (gawk), covers mawk, an additional freely available implementation of awk, and briefly discusses three commercial versions of awk, MKS awk, Thompson Automation awk (tawk), and Videosoft (VSAwk).

Read more...
Abstract: Annotation

sed & awk describes two text processing programs that are mainstays of the UNIX programmers toolbox.

sed is a stream editor for editing streams of text that might be too large to edit as a single file, or that might be generated on the fly as part of a larger data processing step. The most common operation done with sed is substitution, replacing one block of text with another.

awk is a complete programming language. Unlike many conventional languages, awk is data driven -- you specify what kind of data you are interested in and the operations to be performed when that data is found. awk does many things for you, including automatically opening and closing data files, reading records, breaking the records up into fields, and counting the records. While awk provides the features of most conventional programming languages, it also includes some unconventional features, such as extended regular expression matching and associative arrays. sed & awk describes both programs in detail and includes a chapter of example sed and awk scripts.

This edition covers features of sed and awk that are mandated by the POSIX standard. This most notably affects awk, where POSIX standardized a new variable, CONVFMT, and new functions, toupper() and tolower(). The CONVFMT variable specifies the conversion format to use when converting numbers to strings (awk used to use OFMT for this purpose). The toupper() and tolower() functions each take a (presumably mixed case) string argument and return a new version of the string with all letters translated to the corresponding case.

In addition, this edition covers GNU sed, newly available since the first edition. It also updates the first edition coverage of Bell Labs nawk and GNU awk (gawk), covers mawk, an additional freely available implementation of awk, and briefly discusses three commercial versions of awk, MKS awk, Thompson Automation awk (tawk), and Videosoft (VSAwk).

Dougherty Dale: author's other books


Who wrote Sed & Awk? Find out the surname, the name of the author of the book and a list of all author's works by series.

Sed & Awk — read online for free the complete book (whole text) full work

Below is the text of the book, divided by pages. System saving the place of the last page read, allows you to conveniently read the book "Sed & Awk" online for free, without having to search again every time where you left off. Put a bookmark, and you can go to the page where you finished reading at any time.

Light

Font size:

Reset

Interval:

Bookmark:

Make
sed & awk, 2nd Edition

Table of Contents

sed & awk, 2nd Edition
Dale Dougherty
Arnold Robbins
Editor
Dale Dougherty

Copyright 2010 O'Reilly Media, Inc.

A Note Regarding Supplemental Files Supplemental files and examples for this - photo 1


A Note Regarding Supplemental Files

Supplemental files and examples for this book can be found at http://examples.oreilly.com/9781565922259/. Please use a standard desktop web browser to access these files, as they may not be accessible from all ereader devices.

All code files or examples referenced in the book will be available online. For physical books that ship with an accompanying disc, whenever possible, weve posted all CD/DVD content. Note that while we provide as much of the media content as we are able via free download, we are sometimes limited by licensing restrictions. Please direct any questions or concerns to .

Dedication

To Miriam, for your love and patience.

Arnold Robbins
Preface

This book is about a set of oddly named UNIX utilities, sed and awk . These utilities have many things in common, including the use of regular expressions for pattern matching. Since pattern matching is such an important part of their use, this book explains UNIX regular expression syntax very thoroughly. Because there is a natural progression in learning from grep to sed to awk, we will be covering all three programs, although the focus is on sed and awk.

Sed and awk are tools used by users, programmers, and system administratorsanyone working with text files. Sed, so called because it is a stream editor, is perfect for applying a series of edits to a number of files. Awk, named after its developers Aho, Weinberger, and Kernighan, is a programming language that permits easy manipulation of structured data and the generation of formatted reports. This book emphasizes the POSIX definition of awk. In addition, the book briefly describes the original version of awk, before discussing three freely available versions of awk and two commercial ones, all of which implement POSIX awk.

The focus of this book is on writing scripts for sed and awk that quickly solve an assortment of problems for the user. Many of these scripts could be called "quick-fixes." In addition, we'll cover scripts that solve larger problems that require more careful design and development.

Scope of This Handbook

, is an overview of the features and capabilities of sed and awk.

, demonstrates the basic operations of sed and awk, showing a progression in functionality from sed to awk. Both share a similar command-line syntax, accepting user instructions in the form of a script.

, describes UNIX regular expression syntax in full detail. New users are often intimidated by these strange expressions, used for pattern matching. It is important to master regular expression syntax to get the most from sed and awk. The pattern-matching examples in this chapter largely rely on grep and egrep .

, begins a three-chapter section on sed. This chapter covers the basic elements of writing a sed script using only a few sed commands. It also presents a shell script that simplifies invoking sed scripts.

, divide the sed command set into basic and advanced commands. The basic commands are commands that parallel manual editing actions, while the advanced commands introduce simple programming capabilities. Among the advanced commands are those that manipulate the hold space, a set-aside temporary buffer.

, begins a five-chapter section on awk. This chapter presents the primary features of this scripting language. A number of scripts are explained, including one that modifies the output of the ls command.

, describes how to use common programming constructs such as conditionals, loops, and arrays.

, describes how to use awk's built-in functions as well as how to write user-defined functions.

, covers a set of miscellaneous awk topics. It describes how to execute UNIX commands from an awk script and how to direct output to files and pipes. It then offers some (meager) advice on debugging awk scripts.

, describes the original V7 version of awk, the current Bell Labs awk, GNU awk (gawk) from the Free Software Foundation, and mawk, by Michael Brennan. The latter three all have freely available source code. This chapter also describes two commercial implementations, MKS awk and Thomson Automation awk ( tawk ), as well as VSAwk, which brings awk-like capabilities to the Visual Basic environment.

, presents two longer, more complex awk scripts that together demonstrate nearly all the features of the language. The first script is an interactive spelling checker. The second script processes and formats the index for a book or a master index for a set of books.

, presents a number of user-contributed scripts that show different styles and techniques of writing scripts for sed and awk.

is a quick reference describing sed's commands and command-line options.

is a quick reference to awk's command-line options and a full description of its scripting language.

.

Availability of sed and awk

Sed and awk were part of Version 7 UNIX (also known as "V7," and "Seventh Edition") and have been part of the standard distribution ever since. Sed has been unchanged since it was introduced.

] to the host ftp.gnu.ai.mit.edu . It is in the file ftp://ftp.gnu.ai.mit.edu/pub/gnu/sed-2.05.tar.gz . This is a tar file compressed with the gzip program, whose source code is available in the same directory. There are many sites world-wide that "mirror" the files from the main GNU distribution site; if you know of one close to you, you should get the files from there. Be sure to use "binary" or "image" mode to transfer the file(s).

In 1985, the authors of awk extended the language, adding many useful features. Unfortunately, this new version remained inside AT&T for several years. It became part of UNIX System V as of Release 3.1. It can be found under the name of nawk, for new awk; the older version still exists under its original name. This is still the case on System V Release 4 systems.

On commercial UNIX systems, such as those from Hewlett-Packard, Sun, IBM, Digital, and others, the naming situation is more complicated. All of these systems have some version of both old and new awk, but what each vendor names each program varies. Some have oawk and awk , others have awk and nawk . The best advice we can give is to check your local documentation.[] Throughout this book, we use the term awk to describe POSIX awk. Specific implementations will be referred to by name, such as "gawk," or "the Bell Labs awk."

discusses three freely available awks (including where to get them), as well as several commercial ones.


Note

Since the first edition of this book, the awk language was standardized as part of the POSIX Command Language and Utilities Standard (P1003.2). All modern awk implementations aim to be upwardly compatible with the POSIX standard.

The standard incorporates features that originated in both new awk and gawk. In this book, you can assume that what is true for one implementation of POSIX awk is true for another, unless a particular version is designated.


Next page
Light

Font size:

Reset

Interval:

Bookmark:

Make

Similar books «Sed & Awk»

Look at similar books to Sed & Awk. We have selected literature similar in name and meaning in the hope of providing readers with more options to find new, interesting, not yet read works.


Reviews about «Sed & Awk»

Discussion, reviews of the book Sed & Awk and just readers' own opinions. Leave your comments, write what you think about the work, its meaning or the main characters. Specify what exactly you liked and what you didn't like, and why you think so.