A
abc.sh, 23
AddSubtract1.sh, 129–130
AlignColumns1.sh, 118–119
aligned-data2.csv, 139
aligned-data.txt, 141
array-from-file.sh, 25–26
array-function.sh, 26–27
array-loops1.sh, 27
Arrays, 24–27
array1.sh, 25
awk command
built-in variables control, 116–117
character sets, 126–127
code sample, 147–149
count occurrences, 135–136
Fields2.sh, 135
Fields3.sh, 137
FixedFieldCount1.sh, 136–137
for loop in, 120–121
Loop.sh in, 120–121
metacharacters, 126–127
multiline records in, 146–147
numeric functions in, 130–132
one-line, 132–133
onlywords.sh, 144–145
printing lines using conditional logic, 127–128
printing the words in, 135
short, 133–134
split() function, 171–172
splitting filenames with, 128
string2date2.sh, 149
test. txt as, 118
VariableColumns.txt, 137
while loop statement, 119–120
working, 117–118
B
“Back tick”, 21–22
bash shell, 3
Bourne shell, 2–3
command substitution of, 21–22
Bourne, Stephen R., 2
break statement, for loop in awk command, 121
bunzip2 command, 54–55
bz files, 55
C
and pipe symbol, 10–11
cd command, 5
Character
control, 103–104
dash, 13
intermediate, 72
sets, 126–127
CheckLogUpdates.sh, 167–168
checkNewUser() function, 60
checkrows.sh, 136
cmp command, 45
ColumnCount1.sh, 123
columnCount variable, 138
columns.txt, 122–123
columns2.txt, 118
joining alternate lines in, 125
columns4.txt, 71–73, 95, 102–103, 143–144
columns5.txt, 78–79
Command substitution (“back tick”), 21–22
CommandSubst.sh, 22
Comma separated values (CSV), 56
continue statement, for loop in awk command, 121–122
Control characters, 103–104
controlchars.txt file, 103–104
controlm.csv dataset, 50
controlm.sh, 50–51
cp command, 29
cpio command, 53–54
csh shell script, 3
CSV. See Comma separated values
C-type shells, 3
currRow, 142
Customers.txt text file, 165
cut command, 20, 30–31, 75, 164
D
Dash character, 13
datacolumns1.sh dataset, 57–58
datacolumns1.txt dataset, 56, 57
data1.csv, 135
data2.csv, 135–136
Datasets
adding values from multiple, 175–176
aligning columns in, 138–140
contents of, 171
counting words in, 104, 142–144
datacolumns1.sh, 57–58
deleting alternate lines in, 122
delim1.txt, 99
displaying only “pure” words in, 144–146
with egrep command, 86–88
even rows in, 141–142
finding empty lines in, 79–80
in fixed number of columns, 137
merging lines in, 122–126
with multiple delimiters, 99
multiple rows in, 139–140
scanning diagonal elements in, 172–175
uneven.sh, 58–59
uneven.txt, 58
working with, 100–104
data.txt file, 133–134
data4.txt with sed command, 107–114
dates2.csv, 148–149
def string, 86
deletelines.sh, 122
delim1.csv, 147
delimiter1.sh, 99
delimiter1.txt, 99
delim1.sh, 147
delim1.txt, 99
diagonal.txt, 172
diff command, 45
digits.sh, 124
digits.txt, 124
divisors() function, 157
Divisors2.sh, 156–158
E
echo command, 19, 20–21, 31, 46, 57
EchoCut.sh, 21
employee.txt, using awk command, 146
env command, 14
Environment variables, 14–16
Error messages, 85
Euclidean algorithm, 154
Executable files, 16–17
Execution time, 66
exp(x) function, 130
F
Factorial.sh, 61–62
Factorial2.sh, 62–63
Factorial3.sh, 63–64
factvalues, 64
fib() function, 153
Fibonacci numbers, calculation of, 152–153
Fibonacci.sh, 152–153
Fields2.sh, 135
Fields3.sh, using awk command, 137
File compression commands
bunzip2 command, 54–55
cpio command, 53–54
gunzip command, 54
gzip command, 54
tar command, 52–53
zip command, 55
File contents, 7–8
File ownership, 12
findkey.sh, 84
findsvg.sh, 84
FixedFieldCount1.sh, 136–137
for loop, 98
in awk command, 120–121
with break statement, 121
next and continue statement, 121–122
-F switch sets, 117
Function
divisors(), 157
exp(x), 130
fib(), 153
gcd(), 156
int(x), 130
items(), 27
lcm(), 156
log(x), 131
rand(), 131–132
sin(x), 131
sqrt(x), 132
srand(x), 132
time(), 132
G
gawk command, 116
gcd() function, 156
GCD of two positive integers, 153–154
gcd.sh, 153–154
genetics.txt, 171–172
Global Regular Expression Print (grep), 66–67
grep command, 66–67, 99, 138, 158
backslash character and, 81
character classes and, 73
-c option in, 74–75
egrep command, 85–88
fgrep command, 85–88
intermediate characters, 72
multiple matches in, 81
simulating relational data with, 164–167
useful options for, 69–73
using back references in, 77–79
and xargs command, 81–84
gunzip command, 54
gzip command, 54
H
Hidden files, 12–13
history command, 5
HOME environment variable, 14
HOSTNAME environment variable, 14
I
if statement, 57
Intermediate characters, 72
Internal field separator (IFS), 24, 56
int(x) function, 130
Invisible files. see Hidden files
items() function, 27
Iterative solutions, for factorial values, 62–64
J
jar command, 161
JoinLines2.sh, 125–126
K
Korn shell, 3
L
lcm() function, 156
lcm.sh, 155–156
linear-combo.sh, 180–181
lines.txt, 68
Linux operating system, 2
Log directory, 74
Logfile, checking updates in, 167–169
log(x) function, 131
LOGNAME environment variable, 14
longfile.txt, 75
Loop.sh in awk command, 120–121
Lowest common multiple (LCM) of two positive integers, 155–156
ls command, 6–7
M
Mac OS X operating system, 2, 3
man command, 4
MasterOrders.sh, 165–166
MasterOrders.txt text file, 165
MatchAlpha1.sh, 127
and character sets, 126–127
in egrep expressions, 86
mixed-data.csv, 138
mixed-data2.csv, 139
mixed-data.sh, 138
mixed-data2.sh, 139–140
mixednumbers.txt, 129
more command, 10
Multiline records processing, 169–170
multiline.txt, 169–170
Multiple commands, 33–34
mylogfile.txt, 168
myzip.sh, 158–159
N
namepairs.csv, 36
names.txt, using paste command, 25, 29–30
nawk command, 116
Nested loops, 27–28
nestedloops.sh, 27–28
nocontrol1.txt file, 104
node_modules directory, 83
numbers.txt, 171
numbers.txt file, 92
Numeric functions, in awk command, 130–132
O
od command, 45–46
One-line awk command, 132–133
One-line sed command, 107–114
One Space.txt, 13
P
paste command, 29–30
PATH environment variable, 15
Patterns1.sh, 126
POSIX character, 47
Postfix arithmetic operators, 129–130
Prime divisors, 156–158
Printing lines, 101–102
using conditional logic, 127–128
Problematic filenames, 13
products.txt, 127–128
PurchaseOrders.txt text file, 165
pwd command, 4
Q
quotes3.csv, 147
R
rainfall1.sh, 175–176
rainfall12.sh, 176–177
rand() function, 131–132
Recursion, 61–62
Recursion-based solutions, 151
Regular expressions, 31, 67, 78
RemoveColumn.sh, 140–141
RemoveColumns.txt, 126
rowCount variable, 140
S
Scanning diagonal elements, in datasets, 172–175
searchstrings.sh, 159–160
back references in, 104–105
character classes and, 102–103
data4.txt with, 107–114
delimiter1.sh, 99
execution cycle, 92
matching string using, 92–93
one-line, 107–114
“pure” words in, 105–107
search and replace with, 96–98
substituting string using, 93–96
useful switches in, 99–100
world with, 109
Semicolon, to separate commands, 19–20
Shebang, 18
SHELL environment variable, 15
Shell scripts, 17–19
abc.sh, 23
AlignColumns1.sh, 118
checkrows2.sh, 136
diagonal.sh, 172–173
Divisors2.sh, 156–158
Fibonacci.sh, 152–153
function, 59–61
gcd.sh, 153–154
genetics.sh, 172
joinlines.sh, 30
lcm.sh, 155–156
linear-combo.sh, 180–181
multiline.sh, 170
rainfall1.sh, 175–176
rainfall12.sh, 176–177
recursion and, 61–62
setting environment variables in, 22–24
sourcing/dotting, 23–24
sumrows.sh, 171
WordCounts1.sh, 142–143
WordCounts2.sh, 143
sin(x) function, 131
skuprices.txt, 162
skusold.txt, 80
skutotals.sh, 161–162
skuvalues.txt, 80
sort command, 42–44, 66, 106, 145
split command, 41–42
SplitFilename2.sh, 128
split() function, 130, 171–172, 182
SplitName1.sh, 31
sqrt(x) function, 132
srand(x) function, 132
sub-rows-cols.sh, 141–142
sub-rows-cols.txt, 141
T
Tablet string, 128
tar command, 52–53
tee command, 52
test1.csv, 88–89
testing.tar file, 53
testing.tar.gz, 53
test.sh, 18
test4.txt file
doubled-spaced lines, 101–102
as single line, 123–124
Thompson, Ken, 2
time() function, 132
Torvalds, Linus, 2
tr command, 46–49
U
uneven.sh dataset, 58–59
uneven.txt dataset, 58
Unix
operating system, 2–3
pipe symbol, 49
unzip command, 161
update2.sh, 98
USER environment variable, 15
VariableColumns.txt, 140
W
wc command, 7
whatis command, 17
where command, 17
whereis command, 17
which command, 16
while loop statement, 119–120
Whitespaces, 20
WordCountInFile.sh file, 104
WordCounts1.sh, 142–143
WordCounts2.sh, 143
X
xargs command, 52, 59, 73, 81–85
Z
zcat command, 55
zip command, 55