Linux下的shell编程入门

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case $USER in beichen) Echo You are beichen! ;; liangnian) echo You are liangnian ; // echo Welcome! ;; // root) echo You are root!:echo Welcome! ;; //
?D?D (test)
shell
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test
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[beichen@localhost bin]$ P1 this is a test program // 5 Program name is /home/beichen/bin/P1 // There are totally 5 parameters passed to this program // The last is 0 // The parameters are this is a test program //
$? ----
shell
shell
0
0
$* ----
P1: echo Program name is $0 echo There are totally $# parameters passed to this program echo The last is $? echo The parameters are $*
del #name: del #author: liangnian #this program to compress a file to the dustbin if test $# -eq 0 then
echo Please specify a file! else gzip $1 // mv $1.gz $HOME/dustbin // echo File $1 is deleted ! fi
[beichen@localhost bin]$.f_rmgz /home/beichen/dustbin/nessus-4.0.0.2.tar.gz has been deleted! /home/beichen/dustbin/gftp-2.2.1.tar.gz has been deleted! While
Linux shell
shell
shell
Shell Shell
C Linux
Linux
shell
1
date,
#Program date
#usageto ::show the date in this way ( )
echo Mr.$USER,Today is:
echo date +%B%d%A
echo Whish you a lucky day !
[beichen@localhost /]$ .date
Mr.beichen,Today is:
January 13 Friday
Whish you a lucky day !
date
.
shell
shell
ls
1
1 $1. C
0
0
$1
2
$0
Linux 1
shell
Shell
$N
N
$0
$1
$0
$# ----
2
chmod +x date
ls
[beichen@localhost bin]$ date
Mr.beichen,Today is:
January 13 Friday
Whish you a lucky day !
bin
bin shell .
[beichen@localhost bin]$ PATH=$PATH:$HOME/bin
*) echo Who are you?$USER? ;; esac
[liangnian@localhost bin]$ test
You are liangnian
Welcome!
shell
shell
(
$HOME
/home/beichen, bin
)
date
shell :
[beichen@localhost /]$ bash date
Mr.beichen,Today is:
January 13 Friday
Whish you a lucky day !
Linux
chmod +x date date
shell
for
while
until
for
for
in
do
done
for
.gz #delete all file with extension of gz in the dustbin for I in $HOME/dustbin/*.gz do rm ?Cf $i echo $i has been deleted! done
while do
done while
until until
do
do done
done
do done
:
#test until
#add from 1 to 100
total=0
num=0
until test num ?Ceq 100
do
total=`expr $total + $num` //
,
num=`expr $num+1`
done
echo The result is $total
[beichen@localhost bin]$until
The result is 5050!
Shell If
if
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if
case
elif
2 then
elif
3 then
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fi
Linux if
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case