Unix Shells By Example 4th Edition
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UNIX <strong>Shells</strong> by <strong>Example</strong> Fourth <strong>Edition</strong><br />
Table of Contents<br />
Copyright<br />
Preface<br />
ACKNOWLEDGMENTS<br />
Chapter 1. Introduction to UNIX/Linux <strong>Shells</strong><br />
1.1. What Is UNIX? What Is Linux? A Little History<br />
1.2. Definition and Function of a Shell<br />
1.3. History of the Shell<br />
1.4. System Startup and the Login Shell<br />
1.5. Processes and the Shell<br />
1.6. The Environment and Inheritance<br />
1.7. Executing Commands from Scripts<br />
Chapter 2. Shell Programming QuickStart<br />
2.1. Taking a Peek at Shell Scripts<br />
2.2. Sample Scripts: Comparing the Major <strong>Shells</strong><br />
2.3. The C and TC Shell Syntax and Constructs<br />
2.4. The Bourne Shell Syntax and Constructs<br />
2.5. The Korn Shell Constructs<br />
2.6. The Bash Shell Constructs<br />
Chapter 3. Regular Expressions and Pattern Matching<br />
3.1. Regular Expressions<br />
3.2. Combining Regular Expression Metacharacters<br />
Chapter 4. The grep Family<br />
4.1. The grep Command<br />
4.2. grep <strong>Example</strong>s with Regular Expressions<br />
4.3. grep with Options<br />
4.4. grep with Pipes<br />
4.5. egrep (Extended grep)<br />
4.6. fgrep (Fixed grep or Fast grep)
4.7. Linux and GNU grep<br />
4.8. GNU Basic grep (grep -G) with Regular Expressions<br />
4.9. grep -E or egrep (GNU Extended grep)<br />
4.10. Fixed grep (grep -F and fgrep)<br />
4.11. Recursive grep (rgrep, grep -R)<br />
4.12. GNU grep with Options<br />
4.13. grep with Options (UNIX and GNU)<br />
LAB 1: grep EXERCISE<br />
Chapter 5. sed, the Streamlined Editor<br />
5.1. What Is sed ?<br />
5.2. Versions of sed<br />
5.3. How Does sed Work?<br />
5.4. Regular Expressions<br />
5.5. Addressing<br />
5.6. Commands and Options<br />
5.7. Error Messages and Exit Status<br />
5.8. Metacharacters<br />
5.9. sed <strong>Example</strong>s<br />
5.10. sed Scripting<br />
LAB 2: sed EXERCISE<br />
Chapter 6. The awk Utility<br />
6.1. What's awk? What's nawk? What's gawk?<br />
6.2. awk's Format<br />
6.3. How awk Works<br />
6.4. Formatting Output<br />
6.5. awk Commands from Within a File<br />
6.6. Records and Fields<br />
6.7. Patterns and Actions<br />
6.8. Regular Expressions<br />
6.9. awk Commands in a Script File<br />
6.10. Review
LAB 3: awk EXERCISE<br />
6.11. Comparison Expressions<br />
6.12. Review<br />
LAB 4: awk EXERCISE<br />
6.13. Variables<br />
6.14. Redirection and Pipes<br />
6.15. Pipes<br />
6.16. Review<br />
LAB 5: nawk EXERCISE<br />
6.17. Conditional Statements<br />
6.18. Loops<br />
6.19. Program Control Statements<br />
6.20. Arrays<br />
6.21. awk Built-In Functions<br />
6.22. Built-In Arithmetic Functions<br />
6.23. User-Defined Functions (nawk)<br />
6.24. Review<br />
LAB 6: nawk EXERCISE<br />
6.25. Odds and Ends<br />
LAB 7: nawk EXERCISE<br />
6.26. awk Built-In Functions<br />
Chapter 7. The Interactiven Bourne Shell<br />
7.1. Introduction<br />
7.2. The Environment<br />
7.3. The Command Line<br />
7.4. Shell Metacharacters (Wildcards)<br />
7.5. Filename Substitution<br />
7.6. Variables<br />
7.7. Quoting<br />
7.8. Command Substitution<br />
7.9. An Introduction to Functions
7.10. Standard I/O and Redirection<br />
7.11. Pipes<br />
7.12. The here document and Input<br />
Chapter 8. Programming the Bourne Shell<br />
8.1. Introduction<br />
8.2. Reading User Input<br />
8.3. Arithmetic<br />
8.4. Positional Parameters and Command-Line Arguments<br />
8.5. Conditional Constructs and Flow Control<br />
8.6. Looping Commands<br />
8.7. Functions<br />
8.8. Trapping Signals<br />
8.9. The Command Line<br />
8.10. Shell Invocation Options<br />
LAB 8: BOURNE SHELL-GETTING STARTED<br />
LAB 9: METACHARACTERS<br />
LAB 10: REDIRECTION<br />
LAB 11: FIRST SCRIPT<br />
LAB 12: COMMAND-LINE ARGUMENTS<br />
LAB 13: GETTING USER INPUT<br />
LAB 14: CONDITIONAL STATEMENTS<br />
LAB 15: CONDITIONALS AND FILE TESTING<br />
LAB 16: THE case STATEMENT<br />
LAB 17: LOOPS<br />
LAB 18: FUNCTIONS<br />
Chapter 9. The Interactive C and TC <strong>Shells</strong><br />
9.1. Introduction<br />
9.2. The Environment<br />
9.3. The C/TC Shell Command Line<br />
9.4. Aliases<br />
9.5. Manipulating the Directory Stack
9.6. Job Control<br />
9.7. Shell Metacharacters<br />
9.8. Filename Substitution<br />
9.9. Redirection and Pipes<br />
9.10. Variables<br />
9.11. Command Substitution<br />
9.12. Quoting<br />
9.13. New Features of the Interactive TC Shell<br />
9.14. The TC Shell Command Line<br />
9.15. TC Shell Command, Filename, and Variable Completion<br />
9.16. TC Shell Spelling Correction<br />
9.17. TC Shell Aliases<br />
9.18. TC Shell Job Control<br />
9.19. Printing the Values of Variables in the TC Shell<br />
9.20. TC Shell Built-In Commands<br />
LAB 19: THE TC SHELL-GETTING STARTED<br />
LAB 20: HISTORY<br />
LAB 21: SHELL METACHARACTERS<br />
LAB 22: REDIRECTION<br />
LAB 23: VARIABLES AND ARRAYS<br />
Chapter 10. Programming the C and TC <strong>Shells</strong><br />
10.1. Introduction<br />
10.2. Reading User Input<br />
10.3. Arithmetic<br />
10.4. Debugging Scripts<br />
10.5. Command-Line Arguments<br />
10.6. Conditional Constructs and Flow Control<br />
10.7. Looping Commands<br />
10.8. Interrupt Handling<br />
10.9. setuid Scripts<br />
10.10. Storing Scripts
10.11. Built-In Commands<br />
LAB 24: C/TC SHELLS-GETTING STARTED<br />
LAB 25: SHELL METACHARACTERS<br />
LAB 26: REDIRECTION<br />
LAB 27: FIRST SCRIPT<br />
LAB 28: GETTING USER INPUT<br />
LAB 29: COMMAND-LINE ARGUMENTS<br />
LAB 30: CONDITIONALS AND FILE TESTING<br />
LAB 31: THE switch STATEMENT<br />
LAB 32: LOOPS<br />
Chapter 11. The Interactive Korn Shell<br />
11.1. Introduction<br />
11.2. The Environment<br />
11.3. The Command Line<br />
11.4. Commenting and Filename Expansion<br />
11.5. Aliases<br />
11.6. Job Control<br />
11.7. Metacharacters<br />
11.8. Filename Substitution (Wildcards)<br />
11.9. Variables<br />
11.10. Quoting<br />
11.11. Command Substitution<br />
11.12. Functions<br />
11.13. Standard I/O and Redirection<br />
11.14. Pipes<br />
11.15. Timing Commands<br />
Chapter 12. Programming the Korn Shell<br />
12.1. Introduction<br />
12.2. Reading User Input<br />
12.3. Arithmetic<br />
12.4. Positional Parameters and Command-Line Arguments
12.5. Conditional Constructs and Flow Control<br />
12.6. Looping Commands<br />
12.7. Arrays<br />
12.8. Functions<br />
12.9. Trapping Signals<br />
12.10. Coprocesses<br />
12.11. Debugging<br />
12.12. The Command Line<br />
12.13. Security<br />
12.14. Built-In Commands<br />
12.15. Korn Shell Invocation Arguments<br />
LAB 33: KORN SHELL-GETTING STARTED<br />
LAB 34: HISTORY<br />
LAB 35: ALIASES AND FUNCTIONS<br />
LAB 36: SHELL METACHARACTERS<br />
LAB 37: TILDE EXPANSION, QUOTES, AND COMMAND<br />
SUBSTITUTION<br />
LAB 38: REDIRECTION<br />
LAB 39: JOB CONTROL<br />
LAB 40: WRITING THE info SHELL SCRIPT<br />
LAB 41: VARIABLE EXPANSION OF SUBSTRINGS<br />
LAB 42: THE lookup SCRIPT<br />
LAB 43: USING typeset<br />
LAB 44: THE if/else CONSTRUCT AND THE let COMMAND<br />
LAB 45: THE case STATEMENT<br />
LAB 46: THE select LOOP<br />
LAB 47: AUTOLOADING FUNCTIONS<br />
Chapter 13. The Interactive Bash Shell<br />
13.1. Introduction<br />
13.2. The Environment<br />
13.3. The Command Line
13.4. Job Control<br />
13.5. Command-Line Shortcuts<br />
13.6. Aliases<br />
13.7. Manipulating the Directory Stack<br />
13.8. Metacharacters (Wildcards)<br />
13.9. Filename Substitution (Globbing)<br />
13.10. Variables<br />
13.11. Quoting<br />
13.12. Command Substitution<br />
13.13. Arithmetic Expansion<br />
13.14. Order of Expansion<br />
13.15. Arrays<br />
13.16. Functions<br />
13.17. Standard I/O and Redirection<br />
13.18. Pipes<br />
13.19. Shell Invocation Options<br />
13.20. Shell Built-In Commands<br />
LAB 48: bash SHELL-GETTING STARTED<br />
LAB 49: JOB CONTROL<br />
LAB 50: COMMAND COMPLETION, HISTORY, AND ALIASES<br />
LAB 51: SHELL METACHARACTERS<br />
LAB 52: REDIRECTION<br />
LAB 53: VARIABLES<br />
Chapter 14. Programming the Bash Shell<br />
14.1. Introduction<br />
14.2. Reading User Input<br />
14.3. Arithmetic<br />
14.4. Positional Parameters and Command-Line Arguments<br />
14.5. Conditional Constructs and Flow Control<br />
14.6. Looping Commands<br />
14.7. Functions
14.8. Trapping Signals<br />
14.9. Debugging<br />
14.10. The Command Line<br />
14.11. bash Options<br />
14.12. Shell Built-In Commands<br />
LAB 54: bash SHELL-FIRST SCRIPT<br />
LAB 55: COMMAND-LINE ARGUMENTS<br />
LAB 56: GETTING USER INPUT<br />
LAB 57: CONDITIONAL STATEMENTS<br />
LAB 58: CONDITIONALS AND FILE TESTING<br />
LAB 59: THE case STATEMENT<br />
LAB 60: LOOPS<br />
LAB 61: FUNCTIONS<br />
Chapter 15. Debugging Shell Scripts<br />
15.1. Introduction<br />
15.2. Style Issues<br />
15.3. Types of Errors<br />
15.4. Probable Causes for Syntax Errors<br />
15.5. Tracing with Shell Options and the set Command<br />
15.6. Summary<br />
Chapter 16. The System Administrator and the Shell<br />
16.1. Introduction<br />
16.2. The Superuser<br />
16.3. Becoming a Superuser with the su Command<br />
16.4. Boot Scripts<br />
16.5. Summary<br />
Appendix A. Useful UNIX/Linux Utilities for Shell Programmers<br />
apropos-searches the whatis database for strings<br />
arch-prints the machine architecture (see uname -m)<br />
at, batch-executes commands at a later time<br />
awk-pattern scanning and processing language
anner-makes posters<br />
basename-with a directory name delivers portions of the pathname<br />
bash-GNU Bourne Again Shell<br />
bc-processes precision arithmetic<br />
bdiff-compares two big files<br />
cal-displays a calendar<br />
cat-concatenates and displays files<br />
chfn-changes the finger information<br />
chmod-changes the permissions mode of a file<br />
chown-changes owner of file<br />
chsh-changes your login shell<br />
clear-clears the terminal screen<br />
cmp-compares two files<br />
compress-compress, uncompress, zcat compress, uncompress files, or<br />
display expanded files<br />
cp-copies files<br />
cpio-copies file archives in and out<br />
cron-the clock daemon<br />
crypt-encodes or decodes a file<br />
cut-removes selected fields or characters from each line of a file<br />
date-displays the date and time or sets the date<br />
dd-converts a file while copying it<br />
diff-compares two files for differences<br />
dos, xdos, dosexec, dosdebug-a Linux DOS emulator that runs MS-<br />
DOS and MS-DOS programs under Linux<br />
df-summarizes free disk space<br />
du-summarizes disk usage<br />
echo-echoes arguments<br />
egrep-searches a file for a pattern using full regular expressions<br />
expr-evaluates arguments as an expression<br />
fgrep-searches a file for a character string
file-determines the type of a file by looking at its contents<br />
find-finds files<br />
finger-displays information about local and remote users<br />
fmt-simple text formatters<br />
fold-folds long lines<br />
ftp-file transfer program<br />
free-displays amount of free and used memory in the system<br />
fuser-identifies processes using files or sockets<br />
gawk-pattern scanning and processing language<br />
gcc, g++-GNU project C and C++ Compiler (v2.7)<br />
getopt(s)-parses command-line options<br />
grep-searches a file for a pattern<br />
groups-prints group membership of user<br />
gzip, gunzip, zcat-compresses or expands files<br />
head-outputs the first ten lines of a file(s)<br />
host-prints information about specified hosts or zones in DNS<br />
id-prints the username, user ID, group name, and group ID<br />
jsh-the standard, job control shell<br />
kill-sends a signal to terminate one or more processes<br />
killall-kills processes by name<br />
less-opposite of more<br />
line-reads one line<br />
ln-creates hard links to files<br />
logname-gets the name of the user running the process<br />
look-displays lines beginning with a given string<br />
lp-sends output to a printer (AT&T)<br />
lpr-sends output to a printer (UCB)<br />
lpstat-prints information about the status of the LP print service (AT&T)<br />
lpq-prints information about the status of the printer (UCB)<br />
ls-lists contents of directory<br />
mail, rmail-reads mail or sends mail to users
mailx-interactive message processing system<br />
make-maintains, updates, and regenerates groups of related programs<br />
and files<br />
man-formats and displays the online manual pages<br />
manpath-determines user's search path for man pages<br />
mesg-permits or denies messages resulting from the write command<br />
mkdir-creates a directory<br />
more-browses or pages through a text file<br />
mtools-utilities to access DOS disks in UNIX<br />
mv-moves or renames files<br />
nawk-pattern scanning and processing language<br />
newgrp-logs into a new group<br />
news-prints news items<br />
nice-runs a command at low priority<br />
nohup-makes commands immune to hangups and quits<br />
od-octal dump<br />
pack, pcat, unpack-compresses and expands files<br />
passwd-changes the login password and password attributes<br />
paste-merges same lines of several files or subsequent lines of one file<br />
pcat-(see pack)<br />
pine-a Program for Internet News and E-mail<br />
pg-displays files one page at a time<br />
pr-prints files<br />
ping-reports if a remote system is reachable and alive<br />
ps-reports process status<br />
pstree-displays a tree of processes<br />
pwd-displays the present working directory name<br />
quota-displays users' disk usage and limits<br />
rcp-remote file copy<br />
rdate-gets the date and time via the network<br />
rgrep-a recursive, highlighting grep program
login-remote login<br />
rm-removes files from directories<br />
rmdir-removes a directory<br />
rsh-starts a remote shell<br />
ruptime-shows the host status of local machines<br />
rwho-who is logged in on local machines<br />
script-creates a typescript of a terminal session<br />
sed-streamlined editor<br />
size-prints section sizes in bytes of object files<br />
sleep-suspends execution for some number of seconds<br />
sort-sorts and/or merges files<br />
spell-finds spelling errors<br />
split-splits a file into pieces<br />
strings-finds any printable strings in an object or binary file<br />
stty-sets the options for a terminal<br />
su-become superuser or another user<br />
sum-calculates a checksum for a file<br />
sync-updates the superblock and sends changed blocks to disk<br />
tabs-sets tab stops on a terminal<br />
tail-displays the tail end of a file<br />
talk-allows you to talk to another user<br />
tar-stores and retrieves files from an archive file, normally a tape device<br />
tee-replicates the standard output<br />
telnet-communicates with a remote host<br />
test-evaluates an expression<br />
time-displays a summary of time used by this shell and its children<br />
timex-times a command; reports process data and system activity<br />
top-displays top CPU processes<br />
touch-updates access time and/or modification time of a file<br />
tput-initializes a terminal or queries the terminfo database<br />
tr-translates characters
true-provides successful exit status<br />
tsort-topological sort<br />
tty-gets the name of the terminal<br />
umask-sets file-creation mode mask for permissions<br />
uname-prints name of current machine<br />
uncompress-restores files to their original state after they have been<br />
compressed using the compress command<br />
uniq-reports on duplicate lines in a file<br />
units-converts quantities expressed in standard scales to other scales<br />
unpack-expands files created by pack<br />
uucp-copies files to another system, UNIX-to-UNIX system copy<br />
uuencode, uudecode-encodes a binary file into ASCII text in order to<br />
send it through e-mail, or converts it back into its original form<br />
wc-counts lines, words, and characters<br />
what-extracts SCCS version information from a file by printing<br />
information found after the @(#) pattern<br />
which-locates a command and displays its pathname or alias (UCB)<br />
whereis-locates the binary, source, and manual page files for a command<br />
(UCB)<br />
who-displays who is logged on the system<br />
write-writes a message to another user<br />
xargs-constructs an argument list(s) and executes a command<br />
zcat-uncompresses a compressed file to standard output; Same as<br />
uncompress c<br />
zipinfo-lists detailed information about a ZIP archive<br />
zmore-file perusal filter for crt viewing of compressed text<br />
Appendix B. Comparison of the <strong>Shells</strong><br />
B.1. The <strong>Shells</strong> Compared<br />
B.2. tcsh versus csh<br />
B.3. bash versus sh<br />
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