Bash-Beginners-Guide

Recommendations

Info

Bash Guide for Beginners ♦ Print the number of arguments. Test with zero, one, three and over ten arguments. 2. Write a script that implements a simple web browser (in text mode), using wget and links -dump to display HTML pages to the user. The user has 3 choices: enter a URL, enter b for back and q to quit. The last 10 URLs entered by the user are stored in an array, from which the user can restore the URL by using the back functionality. Chapter 10. More on variables 130
Chapter 11. Functions In this chapter, we will discuss ♦ What functions are ♦ Creation and displaying of functions from the command line ♦ Functions in scripts ♦ Passing arguments to functions ♦ When to use functions 11.1. Introduction 11.1.1. What are functions? Shell functions are a way to group commands for later execution, using a single name for this group, or routine. The name of the routine must be unique within the shell or script. All the commands that make up a function are executed like regular commands. When calling on a function as a simple command name, the list of commands associated with that function name is executed. A function is executed within the shell in which it has been declared: no new process is created to interpret the commands. Special built-in commands are found before shell functions during command lookup. The special built-ins are: break, :, ., continue, eval, exec, exit, export, readonly, return, set, shift, trap and unset. 11.1.2. Function syntax Functions either use the syntax function FUNCTION { COMMANDS; } or FUNCTION () { COMMANDS; } Both define a shell function FUNCTION. The use of the built-in command function is optional; however, if it is not used, parentheses are needed. The commands listed between curly braces make up the body of the function. These commands are executed whenever FUNCTION is specified as the name of a command. The exit status is the exit status of the last command executed in the body. Common mistakes The curly braces must be separated from the body by spaces, otherwise they are interpreted in the wrong way. The body of a function should end in a semicolon or a newline. Chapter 11. Functions 131
Page 1 and 2:
Bash Guide for Beginners Machtelt G
Page 3 and 4:
Bash Guide for Beginners Table of C
Page 5 and 6:
Bash Guide for Beginners Table of C
Page 7 and 8:
Table of Contents Glossary C.......
Page 9 and 10:
Introduction 1. Why this guide? The
Page 11 and 12:
Revision 1.6 2005-03-01 Revised by:
Page 13 and 14:
Bash Guide for Beginners See Chapte
Page 15 and 16:
Bash Guide for Beginners mia:~> cat
Page 17 and 18:
Bash Guide for Beginners When invok
Page 19 and 20:
More information about the file des
Page 21 and 22:
Built-in commands are necessary to
Page 23 and 24:
• Brace expansion • Tilde expan
Page 25 and 26:
A number of methods can be used; on
Page 27 and 28:
Bash Guide for Beginners stop in ea
Page 29 and 30:
Chapter 2. Writing and debugging sc
Page 31 and 32:
the documentation of your favorite
Page 33 and 34:
Bash Guide for Beginners Comments a
Page 35 and 36:
Bash Guide for Beginners + set +x I
Page 37 and 38:
Chapter 3. The Bash environment In
Page 39 and 40:
Bash Guide for Beginners local pid
Page 41 and 42:
MOZILLA_FIVE_HOME=/usr/lib/mozilla
Page 43 and 44:
Bash Guide for Beginners franky ~>
Page 45 and 46:
the GNU Awk programming language is
Page 47 and 48:
Bash Guide for Beginners 3.2.4. Res
Page 49 and 50:
LINES MACHTYPE MAILCHECK OLDPWD OPT
Page 51 and 52:
two is the second positional parame
Page 53 and 54:
Bash Guide for Beginners 3.3.1. Why
Page 55 and 56:
A correctly-formed brace expansion
Page 57 and 58:
Bash Guide for Beginners If the sub
Page 59 and 60:
of the whitespace characters "space
Page 61 and 62:
Bash Guide for Beginners /dev/hda5
Page 63 and 64:
Bash Guide for Beginners 3.7. Summa
Page 65 and 66:
Two regular expressions may be conc
Page 67 and 68:
LABEL=/ / ext3 defaults 1 1 If this
Page 69 and 70:
cathy ~> ls -ld [[:digit:]]* drwxrw
Page 71 and 72:
Bash Guide for Beginners p Print te
Page 73 and 74:
sandy ~> sed -n '/a text/,/This/p'
Page 75 and 76:
Bash Guide for Beginners # This is
Page 77 and 78:
Chapter 6. The GNU awk programming
Page 79 and 80:
Bash Guide for Beginners 121script.
Page 81 and 82:
Bash Guide for Beginners amd.conf a
Page 83 and 84:
Bash Guide for Beginners record1 re
Page 85 and 86:
Bash Guide for Beginners 6.3.6. The
Page 87 and 88: Chapter 7. Conditional statements I
Page 89 and 90: Bash Guide for Beginners Table 7-2.
Page 91 and 92: Bash Guide for Beginners 7.1.2.2. N
Page 93 and 94: [root@elegance root]# We switch to
Page 95 and 96: Bash Guide for Beginners echo "Prop
Page 97 and 98: Bash Guide for Beginners We use the
Page 99 and 100: Bash Guide for Beginners case EXPRE
Page 101 and 102: Upon successful condition testing,
Page 103 and 104: Bash Guide for Beginners bit better
Page 105 and 106: 8.2. Catching user input 8.2.1. Usi
Page 107 and 108: Bash Guide for Beginners michel ~/t
Page 109 and 110: Bash Guide for Beginners # DO NOT E
Page 111 and 112: File descriptor 5 Bash Guide for Be
Page 113 and 114: Bash Guide for Beginners The result
Page 115 and 116: Bash Guide for Beginners ♦ Compre
Page 117 and 118: Bash Guide for Beginners for i in `
Page 119 and 120: touch pic-`date +%s`.jpg sleep 300
Page 121 and 122: DISKFUL=$(df -h $WEBDIR | grep -v F
Page 123 and 124: ;; 2) $FORTUNE startrek ;; 3) $FORT
Page 125 and 126: [carol@octarine ~/test] ls -a ./ ..
Page 127 and 128: Bash Guide for Beginners 9.7.2. Exa
Page 129 and 130: Chapter 10. More on variables In th
Page 131 and 132: Bash Guide for Beginners [bob in ~]
Page 133 and 134: if [ -z $1 ]; then echo "Usage: $0
Page 135 and 136: 10.3.3. Transformations of variable
Page 137: Bash Guide for Beginners The opposi
Page 141 and 142: The commands after && are only exec
Page 143 and 144: zip2 "$TAR" echo "...done." >> "$LO
Page 145 and 146: Chapter 12. Catching signals In thi
Page 147 and 148: Bash Guide for Beginners maud: ~> k
Page 149 and 150: Bash Guide for Beginners 2. Write a
Page 151 and 152: Bash Guide for Beginners jobs kill
Page 153 and 154: if [ $i -eq 5 ] ArrowUp+Enter or !!
Page 155 and 156: cd Change directory. cdp/cdplay An
Page 157 and 158: Bash Guide for Beginners gimp grep
Page 159 and 160: Send and receive mail. man Read man
Page 161 and 162: Bash Guide for Beginners rsh RPM Pa
Page 163 and 164: W Bash Guide for Beginners w Show w
Page 165 and 166: Index A aliases Section 3.5.1 ANSI-
Page 167 and 168: Bash Guide for Beginners Section 3.
Page 169 and 170: J Bash Guide for Beginners K kill k
Page 171 and 172: eadonly Section 10.1.3 regular expr
Page 173: Bash Guide for Beginners vi(m) Sect
show all

Bash-Beginners-Guide

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?