Unix Shell Programming Third Edition phần 4 pptx
Unix Shell Programming Third Edition phần 4 pptx
... sticky area
that is a frequent source of shell programming errors. It's good to really understand the principles
here to save yourself a lot of programming headaches in the future.
There ... are some sample uses of on:
$ who
root console Jul 8 10:37
barney tty03 Jul 8 12:38
fred tty 04 Jul 8 13 :40
joanne tty07 Jul 8 09:35
tony tty19 Jul 8 08:30
lulu tty23 Jul 8 09:55
3 c d e
2 d...
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 ... memo2
request id is laser1- 34 (standard input)
$ run memo3
request id is laser1-35 (standard input)
$ run memo4
request id is laser1-36 (standard input)
$
Incidentally, the shell per...
Unix Shell Programming Third Edition phần 10 pptx
...
Bash shell
beginning of line, matching 2nd
bg command 2nd 3rd 4th 5th 6th
books
AWK Programming Language, The
Learning Pearl
Programming Pearl
Unix C Shell Field Guide, The
Unix in ... Shell Field Guide, The
Unix in a Nutshell[colon] System V Edition
Unix Programmer's Manual, Volume II
Unix Programming Environment, The
Bourne shell
Bourne, S...
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, 2003
ISBN
: 0-672-3 249 0-3
Pages
: 45 6
Slots
: 1
Unix Shell Programming ... shell, such as
bash. Three are covered in the third edition of Unix Shell Programming. It begins with a generalized
tutorial of Unix and tools and then mov...
Unix Shell Programming Third Edition phần 2 pot
... occurrences of " ;Unix& quot; in the text to " ;UNIX. " This can be easily
done in sed as follows:
$ sed 's /Unix/ UNIX/' intro Substitute Unix with UNIX
The UNIX operating system ... at the output from the who command:
$ who
root console Feb 24 08: 54
steve tty02 Feb 24 12:55
george tty08 Feb 24 09:15
dawn tty10 Feb 24 15:55
$
As shown, currently four people...
Unix Shell Programming Third Edition phần 3 docx
... "What Is the Shell? ," you should realize that whenever you
type something like
who | wc -l
that you are actually programming in the shell! That's because the shell is interpreting ... into
detail on the quoting mechanisms in the shell.
Variables
Like virtually all programming languages, the shell allows you to store values into variables. A shell
variable begin...
Unix Shell Programming Third Edition phần 6 ppt
... $number2
done
$ cat data
12 34 7960
593 -595
395 3 04
32 34 999
-3 94 -49 3
$ align data
12 34 7960
593 -595
395 3 04
32 34 999
-3 94 -49 3
$
In Chapters 12, 14, and 15 you'll see more uses for printf. ... the subshell, whereas the
list of local variables does not (see Figure 11 .4) .
Figure 11 .4. Execution of vartest3.
Now it's time for another question: What do you th...
Unix Shell Programming Third Edition phần 7 pdf
... 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 shells or subshells that are executing ... sorted_data & Send it to the background
[1] 342 3 Job number & process id from the shell
$ date Do some other work
Wed Oct 2 15:05 :42 EDT 2002
$ wait 342 3 Now wait for the sort...
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 ... Variables
There are three different "types" of parameters: shell variables, special parameters, and positional
parameters.
Shell Variables
A shell variable name must sta...