CEG 233: Linux and Windows

Course Content in Detail

The following is an edited version of the Table of Contents of our textbook A Practical Guide to Linux Commands, Editors, and Shell Programming by Mark G Sobell. A strike though implies that that topic is not part of the course. Note that we include some topics that are not in the book. Note, in particular, that our course covers corresponding topics of Windows also.

Chapter 1: Welcome to Linux 1

The GNU–Linux Connection 2
The History of GNU–Linux 2
The Code Is Free 4
Have Fun! 5
The Heritage of Linux: UNIX 5
What Is So Good About Linux? 6
Why Linux Is Popular with Hardware Companies and Developers 7
Linux Is Portable 8
Standards 8
The C Programming Language 9
Overview of Linux 10
Linux Has a Kernel Programming Interface 10
Linux Can Support Many Users 10
Linux Can Run Many Tasks 11
Linux Provides a Secure Hierarchical File system 11
The Shell: Command Interpreter and Programming Language 12
A Large Collection of Useful Utilities 14
Interprocess Communication 14
System Administration 14
Additional Features of Linux 15
GUIs: Graphical User Interfaces 15
(Inter)networking Utilities 16
Software Development 16
Chapter Summary 16
Exercises 17

PART I The Linux Operating System 19

Chapter 2: Getting Started 21

Conventions Used in This Book 22
Logging In 24
Logging In from a Terminal 24
Logging In Remotely: Terminal Emulation, ssh, and telnet 25
Working with the Shell 25
Which Shell Are You Running? 26
Correcting Mistakes 26
Curbing Your Power: Superuser Access 28
Getting the Facts: Where to Find Documentation 29
The ––help Option 29
man: Displays the System Manual 30
info: Displays Information About Utilities 32
HOWTOs: Finding Out How Things Work 34
Using the Internet to Get Help 34
More About Logging In 35
What to Do If You Cannot Log In 36
Logging Out 36
~~Using Virtual Consoles 36~~
~~Changing Your Password 37~~
Chapter Summary 38
Exercises 39
Advanced Exercises 39

Chapter 3: Command Line Utilities 41

Special Characters 42
Basic Utilities 43
ls: Lists the Names of Files 43
cat: Displays a Text File 44
rm: Deletes a File 44
less Is more: Displaying a Text File One Screen at a Time 45
hostname: Displays the System Name 45
Working with Files 45
cp: Copies a File 45
mv: Changes the Name of a File 46
~~lpr: Prints a File 47~~
grep: Finds a String 48
head: Displays the Beginning of a File 49
tail: Displays the End of a File 49
sort: Displays a File in Order 50
uniq: Removes Duplicate Lines from a File 51
diff: Compares Two Files 51
file: Tests the Contents of a File 52
| (Pipe): Communicates Between Processes 52
Four More Utilities 53
echo: Displays Text 53
date: Displays the Time and Date 54
script: Records a Linux Session 54
unix2dos: Converts Linux Files to Windows Format 55
Compressing and Archiving Files 56
bzip2: Compresses a File 56
bunzip2 and bzcat: Decompress a File 57
gzip: Compresses a File 58
tar: Packs and Unpacks Files 58
Locating Commands 61
which and whereis: Locate a Utility 61
apropos: Searches for a Keyword 62
slocate: Searches for a File 63
Obtaining User and System Information 63
who: Lists Users on the System 64
~~finger: Lists Users on the System 64~~
w: Lists Users on the System 66
Communicating with Other Users 67
~~write: Sends a Message 67~~
~~mesg: Denies or Accepts Messages 68~~
Email 69
Chapter Summary 69
Exercises 72
Advanced Exercises 73

Chapter 4: The Linux Filesystem 75

The Hierarchical Filesystem 76
Directory and Ordinary Files 77
Filenames 78
mkdir: Creates a Directory 80
The Working Directory 81
Home Directory 82
Absolute Pathnames 83
Relative Pathnames 84
Important Standard Directories and Files 86
Working with Directories 88
rmdir: Deletes a Directory 88
Pathnames 89
mv, cp: Moves or Copies a File 90
mv: Moves a Directory 90
Access Permissions 91
ls –l: Displays Permissions 91
chmod: Changes Access Permissions 92
Setuid and Setgid Permissions 94
Directory Access Permissions 94
Links 96
Hard Links 97
Symbolic Links 99
rm: Removes a Link 101
Chapter Summary 102
Exercises 103
Advanced Exercises 105

Chapter 5: The Shell 107

The Command Line 108
Syntax 108
Processing the Command Line 111
Executing the Command Line 113
Standard Input and Standard Output 113
The Screen as a File 114
The Keyboard and Screen as Standard Input and Standard Output 115
Redirection 116
Pipes 122
Running a Program in the Background 125
Filename Generation/Pathname Expansion 127
The ? Special Character 128
The * Special Character 129
The [] Special Characters 130
Builtins 132
Chapter Summary 133
Utilities and Builtins Introduced in This Chapter 134
Exercises 134
Advanced Exercises 136

PART II The Editors 137

Chapter 6: The vim Editor 139

History 140
Tutorial: Creating and Editing a File with vim 141
Starting vim 141
Command and Input Modes 142
Entering Text 144
Getting Help 144
Ending the Editing Session 147
The compatible Parameter 148
Introduction to vim Features 148
Online Help 149
Modes of Operation 149
The Display 150
Correcting Text as You Insert It 151
Work Buffer 151
Line Length and File Size 151
Windows 151
File Locks 152
Abnormal Termination of an Editing Session 152
Recovering Text After a Crash 153
Command Mode: Moving the Cursor 154
Moving the Cursor by Characters 155
Moving the Cursor to a Specific Character 155
Moving the Cursor by Words 156
Moving the Cursor by Lines 156
Moving the Cursor by Sentences and Paragraphs 157
Moving the Cursor Within the Screen 157
Viewing Different Parts of the Work Buffer 158
Input Mode 158
Inserting Text 158
Appending Text 159
Opening a Line for Text 159
Replacing Text 159
Quoting Special Characters in Input Mode 159
Command Mode: Deleting and Changing Text 160
Undoing Changes 160
Deleting Characters 160
Deleting Text 160
Changing Text 162
Replacing Text 163
Changing Case 163
Searching and Substituting 164
Searching for a Character 164
Searching for a String 164
Substituting One String for Another 166
Miscellaneous Commands 170
Join 170
Status 171
. (Period) 171
Yank, Put, and Delete Commands 171
The General-Purpose Buffer 171
~~Named Buffers 172~~
~~Numbered Buffers 173~~
Reading and Writing Files 174
Reading Files 174
Writing Files 174
Identifying the Current File 175
Setting Parameters 175
Setting Parameters from Within vim 175
Setting Parameters in a Startup File 176
The .vimrc Startup File 176
Parameters 177
Advanced Editing Techniques 180
Using Markers 180
Editing Other Files 181
~~Macros and Shortcuts 182~~
~~Executing Shell Commands from Within vim 182~~
~~Units of Measure 184~~
Character 184
Word 185
Blank-Delimited Word 185
Line 185
Sentence 186
Paragraph 186
Window 187
Repeat Factor 187
Chapter Summary 188
Exercises 193
Advanced Exercises 194

Chapter 7: The emacs Editor 195

History 196
Evolution 196
emacs Versus vim 197
Tutorial: Getting Started with emacs 198
Starting emacs 198
Stopping emacs 199
Inserting Text 199
Deleting Characters 199
Moving the Cursor 200
Editing at the Cursor Position 202
Saving and Retrieving the Buffer 203
Basic Editing Commands 204
Keys: Notation and Use 204
Key Sequences and Commands 205
META-x: Running a Command Without a Key Binding 205
Numeric Arguments 205
Point and the Cursor 206
Scrolling Through a Buffer 206
Erasing Text 207
Searching 207
Online Help 209
Advanced Editing 212
Undoing Changes 212
Mark and Region 213
Cut and Paste: Yanking Killed Text 215
Inserting Special Characters 216
Global Buffer Commands 217
Files 219
Buffers 220
Windows 222
~~Foreground Shell Commands 224~~
~~Background Shell Commands 224~~
~~Language-Sensitive Editing 225~~
~~Selecting a Major Mode 226~~
Human-Language Modes 226
~~C Mode 229~~
~~Customizing Indention 232~~
~~Comments 233~~
~~Special-Purpose Modes 233~~
~~Customizing emacs 235~~
~~The .emacs Startup File 236~~
~~Remapping Keys 237~~
~~A Sample .emacs File 239~~
~~More Information 240~~
~~Access to emacs 240~~
Chapter Summary 241
Exercises 248
Advanced Exercises 250

PART III The Shells 253

Chapter 8: The Bourne Again Shell 255

Background 256
Shell Basics 257
Startup Files 257
Commands That Are Symbols 260
Redirecting Standard Error 260
Writing a Simple Shell Script 263
Separating and Grouping Commands 267
Job Control 271
Manipulating the Directory Stack 274
Parameters and Variables 277
User-Created Variables 278
Variable Attributes 281
Keyword Variables 283
Special Characters 291
Processes 292
Process Structure 293
Process Identification 293
Executing a Command 294
History 295
Variables That Control History 295
Reexecuting and Editing Commands 297
The Readline Library 305
Aliases 312
Single Versus Double Quotation Marks in Aliases 312
Examples of Aliases 313
Functions 315
Controlling bash Features and Options 318
Command Line Options 318
Shell Features 319
Processing the Command Line 322
History Expansion 323
Alias Substitution 323
Parsing and Scanning the Command Line 323
Command Line Expansion 323
Chapter Summary 332
Exercises 334
Advanced Exercises 336

Chapter 9: The TC Shell 339

PART IV Programming Tools 385

Chapter 10: Programming Tools 387

Chapter 11: Programming the Bourne Again Shell 435

Control Structures 436
if...then 437
if...then...else 440
if...then...elif 442
for...in 449
for 451
while 453
until 456
break and continue 459
case 459
select 466
Here Document 468
File Descriptors 470
Parameters and Variables 474
Array Variables 474
Locality of Variables 475
Special Parameters 478
Positional Parameters 480
Expanding Null and Unset Variables 485
Builtin Commands 487
type: Displays Information About a Command 487
read: Accepts User Input 487
exec: Executes a Command 491
trap: Catches a Signal 493
kill: Aborts a Process 497
getopts: Parses Options 497
A Partial List of Builtins 500
Expressions 501
Arithmetic Evaluation 501
Logical Evaluation (Conditional Expressions) 503
String Pattern Matching 504
Operators 505
Shell Programs 510
A Recursive Shell Script 510
The quiz Shell Script 513
Chapter Summary 520
Exercises 522
Advanced Exercises 524

Chapter 12: The gawk Pattern Processing

Chapter 13: The sed Editor 563

Syntax 564
Arguments 564
Options 564
Editor Basics 565
Addresses 565
Instructions 566
Control Structures 567
The Pattern Space and the Hold Space 568
Examples 568
Chapter Summary 578
Exercises 579

PART V Command Reference 581

Standard Multiplicative Suffixes 586
Common Options 587
The sample Utility 587
sample Very brief description of what the utility does 588
~~aspell Checks a file for spelling errors 589~~
~~at Executes commands at a specified time 593~~
bzip2 Compresses or decompresses files 596
cal Displays a calendar 598
cat Joins and displays files 599
cd Changes to another working directory 601
~~chgrp Changes the group associated with a file 603~~
chmod Changes the access mode (permissions) of a file 604
chown Changes the owner of a file and/or the group the file is associated with 608
cmp Compares two files 610
comm Compares sorted files 612
~~configure Configures source code automatically 614~~
cp Copies files 616
~~cpio Creates an archive or restores files from an archive 619~~
~~crontab Maintains crontab files 624~~
~~cut Selects characters or fields from input lines 627~~
date Displays or sets the system time and date 630
dd Converts and copies a file 633
df Displays disk space usage 636
diff Displays the differences between two files 638
du Displays information on disk usage by file 644
echo Displays a message 647
expr Evaluates an expression 649
file Displays the classification of a file 653
find Finds files based on criteria 655
~~finger Displays information about users 661~~
~~fmt Formats text very simply 664~~
~~fsck Checks and repairs a filesystem 666~~
~~ftp Transfers files over a network 671~~
~~gcc Compiles C and C++ programs 678~~
grep Searches for a pattern in files 683
gzip Compresses or decompresses files 688
head Displays the beginning of a file 691
kill Terminates a process by PID 693
killall Terminates a process by name 695
less Displays text files, one screen at a time 697
ln Makes a link to a file 702
~~lpr Sends files to printers 705~~
ls Displays information about one or more files 708
~~make Keeps a set of programs current 715~~
man Displays documentation for commands 721
mkdir Creates a directory 724
mkfs Creates a filesystem on a device 725
~~Mtools Uses DOS-style commands on files and directories 728~~
mv Renames or moves a file 732
nice Changes the priority of a command 734
~~nohup Runs a command that keeps running after you log out 736~~
od Dumps the contents of a file 737
paste Joins corresponding lines from files 742
~~pr Paginates files for printing 744~~
ps Displays process status 746
~~rcp Copies one or more files to or from a remote system 750~~
~~rlogin Logs in on a remote system 752~~
rm Removes a file (deletes a link) 753
rmdir Removes a directory 755
~~rsh Executes commands on a remote system 756~~
scp Securely copies one or more files to or from a remote system 758
sleep Creates a process that sleeps for a specified interval 760
sort Sorts and/or merges files 762
split Divides a file in into sections 771
ssh Securely executes commands on a remote system 773
strings Displays strings of printable characters 777
~~stty Displays or sets terminal parameters 778~~
tail Displays the last part (tail) of a file 783
tar Stores or retrieves files to/from an archive file 786
tee Copies standard input to standard output and one or more files 791
~~telnet Connects to a remote system over a network 792~~
test Evaluates an expression 794
top Dynamically displays process status 798
touch Changes a file’s access and/or modification time 801
tr Replaces specified characters 804
~~tty Displays the terminal pathname 807~~
~~tune2fs Changes parameters on an ext2 or ext3 filesystem 808~~
umask Establishes the file-creation permissions mask 810
uniq Displays unique lines 812
w Displays information about system users 814
wc Displays the number of lines, words, and bytes 816
which Shows where in PATH a command is located 817
who Displays information about logged-in users 819
~~xargs Converts standard input into command lines 821~~

PART VI Appendixes 825

Appendix A: Regular Expressions 827

Characters 828
Delimiters 828
Simple Strings 828
Special Characters 828
Periods 829
Brackets 829
Asterisks 830
Carets and Dollar Signs 830
Quoting Special Characters 831
Rules 831
Longest Match Possible 831
Empty Regular Expressions 832
Bracketing Expressions 832
The Replacement String 833
Ampersand 833
Quoted Digit 833
Extended Regular Expressions 834
Appendix Summary 835

Appendix B: Help 837

Solving a Problem 838
Finding Linux-Related Information 839
Documentation 839
Useful Linux Sites 840
Linux Newsgroups 841
Mailing Lists 841
Words 841
Software 842
Office Suites and Word Processors 844
Specifying a Terminal 844