Table Of Contentsed & awk
sed & awk
Second Edition
Dale Dougherty and Arnold Robbins
Beijing• Cambridge• Farnham• Köln• Sebastopol • Tokyo
sed & awk, Second Edition
by Dale Dougherty and Arnold Robbins
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[M] [2/10]
To Miriam, for your love and patience.
—Arnold Robbins
Ta ble of Contents
Preface ..................................................................................................................... xi
1: Pow er Tools for Editing ............................................................................. 1
May You Solve Interesting Problems ................................................................. 1
A Str eam Editor ................................................................................................... 3
A Patter n-Matching Pr ogramming Language ..................................................... 5
Four Hurdles to Mastering sed and awk ........................................................... 6
2: Understanding Basic Operations .......................................................... 8
Awk, by Sed and Grep, out of Ed ..................................................................... 8
Command-Line Syntax ..................................................................................... 13
Using sed .......................................................................................................... 15
Using awk ......................................................................................................... 20
Using sed and awk Together ........................................................................... 23
3: Understanding Regular Expression Syntax .................................... 26
That’s an Expression ........................................................................................ 27
A Line-Up of Characters ................................................................................... 29
I Never Metacharacter I Didn’t Like ................................................................ 54
4: Writing sed Scripts .................................................................................... 55
Applying Commands in a Script ...................................................................... 56
A Global Perspective on Addressing ............................................................... 58
Testing and Saving Output .............................................................................. 61
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viii Table of Contents
Four Types of sed Scripts ................................................................................ 64
Getting to the PromiSed Land ......................................................................... 77
5: Basic sed Commands .............................................................................. 78
About the Syntax of sed Commands ............................................................... 78
Comment ........................................................................................................... 79
Substitution ....................................................................................................... 80
Delete ................................................................................................................ 86
Append, Insert, and Change ............................................................................ 87
List ..................................................................................................................... 90
Transfor m .......................................................................................................... 93
Print ................................................................................................................... 94
Print Line Number ............................................................................................ 95
Next ................................................................................................................... 95
Reading and Writing Files ................................................................................ 96
Quit ................................................................................................................. 104
6: Advanced sed Commands ................................................................... 106
Multiline Pattern Space .................................................................................. 107
A Case for Study ............................................................................................. 116
Hold That Line ................................................................................................ 119
Advanced Flow Control Commands ............................................................. 127
To Join a Phrase ............................................................................................. 133
7: Writing Scripts for awk ........................................................................ 137
Playing the Game ........................................................................................... 138
Hello, World ................................................................................................... 138
Awk’s Programming Model ............................................................................ 139
Patter n Matching ............................................................................................ 141
Records and Fields ......................................................................................... 143
Expr essions ..................................................................................................... 147
System Variables ............................................................................................. 151
Relational and Boolean Operators ................................................................ 157
For matted Printing .......................................................................................... 163
Passing Parameters Into a Script ................................................................... 166
Infor mation Retrieval ..................................................................................... 169
