Unix Shell Programming Third Edition phần 2 pot
Unix Shell Programming Third Edition phần 2 pot
... phonebook
Alice Chebba\t973-555 -20 15
Barbara Swingle\t201-555- 925 7
Jeff Goldberg\t201-555-3378
Liz Stachiw\t2 12- 555 -22 98
Susan Goldberg\t201-555-7776
Tony Iannino\t973-555- 129 5
$
The output verifies ... following contents:
$ cat phonebook
Alice Chebba 973-555 -20 15
Barbara Swingle 20 1-555- 925 7
Jeff Goldberg 20 1-555-3378
Liz Stachiw 21 2-555 -22 98
prog1
shortcut
sweeney
$
No...
Unix Shell Programming Third Edition phần 1 doc
...
Index
Unix Shell Programming, Third Edition
By Stephen G. Kochan, Patrick Wood
Publisher
: Sams Publishing
Pub Date
: February 27 , 20 03
ISBN
: 0-6 72- 324 90-3
Pages
: 456
Slots
: 1
Unix Shell Programming ... 5
-rwxr-xr-x 1 steve DP3 725 358 Jun 25 13:31 collect
-rwxr-xr-x 1 steve DP3 725 121 9 Jun 25 13:31 mon
-rwxr-xr-x 2 steve DP3 725 89 Jun 25 13:30 wb
-rwxr-xr-...
Unix Shell Programming Third Edition phần 3 docx
... cut -c 12- 16
date | cut -c5-11 ,25 - | sed 's/\([0-9]\{1 ,2\ }\)/\1,/'
3:
Write the commands to
a.
So you see, even the name of a command can be stored inside a variable. Because the shell ... variables, as shown in the next example:
$ value1=10
$ value2=value1
$ echo $value2
value1 Didn't do that right
$ value2=$value1
$ echo $value2
10 That's better
$
Remember that a...
Unix Shell Programming Third Edition phần 4 pptx
... Pizza' Remove this entry
$ cat phonebook
Alice Chebba 973-555 -20 15
Barbara Swingle 20 1-555- 925 7
Billy Bach 20 1-555-7618
Liz Stachiw 21 2-555 -22 98
to achieve the same result. The double quotes are needed ... fine for this purpose.
Take another look at the output from this command:
$ date
Wed Aug 29 10: 42: 01 EDT 20 02
$
The format of date's output is fixed, a fact that...
Unix Shell Programming Third Edition phần 5 pptx
... continue, so
continue n
done
becomes
for i in 1 2 3 4; do echo $i; done
And you can type it in directly this way:
$ for i in 1 2 3 4; do echo $i; done
1
2
3
4
$
The same rules apply to while and until ... the background
[1] 99 32
$
request id is laser1-85 (standard input)
request id is laser1-87 (standard input)
request id is laser1-88 (standard input)
request id is laser1- 92 (standa...
Unix Shell Programming Third Edition phần 6 ppt
... "%12d %12d\n" $number1 $number2
done
$ cat data
123 4 7960
593 -595
395 304
323 4 999
-394 -493
$ align data
123 4 7960
593 -595
395 304
323 4 999
-394 -493
$
In Chapters 12, 14, and ... current
environment. You can also use them for other purposes:
$ (sort 20 02data -o 20 02data; plotdata 20 02data) &
[1] 3 421
$
The parentheses group the sort and plotdata commands t...
Unix Shell Programming Third Edition phần 7 pdf
... sorted_data & Send it to the background
[1] 3 423 Job number & process id from the shell
$ date Do some other work
Wed Oct 2 15:05: 42 EDT 20 02
$ wait 3 423 Now wait for the sort to finish
$ When ... "" 2
and then execute a subshell, which in turn executes other shell programs as subshells. If an interrupt
signal is then generated, it will have no effect on the s...
Unix Shell Programming Third Edition phần 8 doc
... what shell to start up when
you execute a shell escape. In such cases, you want to make sure that each time you start up a new
shell, you get the shell you want and not an older Bourne shell.
... you to interactive features of
the shell and two shells that have some nice features not found in the POSIX standard shell.
Getting the Right Shell
Most shells follow a convention...
Unix Shell Programming Third Edition phần 9 ppt
... command-line option, or after set –o posix is executed.
Table 15.4. POSIX Shell, Korn Shell, and Bash Compatibility
POSIX Shell
Korn Shell
Bash
ENV file
X
X
POS
vi line edit mode
X
X
X
emacs line ... it's not a reserved word, the shell proceeds to step 3.
2.
Next, the shell checks the command against its function list and executes it if found.3.
The shell checks to...
Unix Shell Programming Third Edition phần 10 pptx
... command 2nd
logical AND operator (-a) 2nd
logical negation operator (!) 2nd
logical OR operator (-o) 2nd
login program 2nd 3rd
login shell 2nd 3rd 4th
getty program 2nd
init program 2nd ... number 2nd
number2 2nd
passing arguments to 2nd 3rd 4th
$# variable 2nd
$* variable 2nd
${n} variable 2nd
phonebook file example 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
shift command...