Bash-Beginners-Guide

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3. If the quota daemon is running, use that information; if not, use find. Create XML-style output from a Tab-separated list in the following form: Meaning very long line with a lot of description meaning another long line Bash Guide for Beginners othermeaning testmeaning more longline looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong lin The output should read: Meaning very long line meaning long line
Chapter 7. Conditional statements In this chapter we will discuss the use of conditionals in Bash scripts. This includes the following topics: ♦ The if statement ♦ Using the exit status of a command ♦ Comparing and testing input and files ♦ if/then/else constructs ♦ if/then/elif/else constructs ♦ Using and testing the positional parameters ♦ Nested if statements ♦ Boolean expressions ♦ Using case statements 7.1. Introduction to if 7.1.1. General At times you need to specify different courses of action to be taken in a shell script, depending on the success or failure of a command. The if construction allows you to specify such conditions. The most compact syntax of the if command is: if TEST-COMMANDS; then CONSEQUENT-COMMANDS; fi The TEST-COMMAND list is executed, and if its return status is zero, the CONSEQUENT-COMMANDS list is executed. The return status is the exit status of the last command executed, or zero if no condition tested true. The TEST-COMMAND often involves numerical or string comparison tests, but it can also be any command that returns a status of zero when it succeeds and some other status when it fails. Unary expressions are often used to examine the status of a file. If the FILE argument to one of the primaries is of the form /dev/fd/N, then file descriptor "N" is checked. stdin, stdout and stderr and their respective file descriptors may also be used for tests. 7.1.1.1. Expressions used with if The table below contains an overview of the so-called "primaries" that make up the TEST-COMMAND command or list of commands. These primaries are put between square brackets to indicate the test of a conditional expression. Table 7-1. Primary expressions Primary Meaning [ -a FILE ] True if FILE exists. Chapter 7. Conditional statements 79
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Bash Guide for Beginners Table of C
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Table of Contents Glossary C.......
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Introduction 1. Why this guide? The
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Revision 1.6 2005-03-01 Revised by:
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Bash Guide for Beginners See Chapte
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• Brace expansion • Tilde expan
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A number of methods can be used; on
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Chapter 2. Writing and debugging sc
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the documentation of your favorite
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Bash Guide for Beginners Comments a
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Chapter 11. Functions In this chapt
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zip2 "$TAR" echo "...done." >> "$LO
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Bash Guide for Beginners 2. Write a
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Bash Guide for Beginners jobs kill
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if [ $i -eq 5 ] ArrowUp+Enter or !!
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cd Change directory. cdp/cdplay An
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Bash Guide for Beginners gimp grep
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Send and receive mail. man Read man
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Index A aliases Section 3.5.1 ANSI-
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J Bash Guide for Beginners K kill k
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eadonly Section 10.1.3 regular expr
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Bash Guide for Beginners vi(m) Sect
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