!/bin/bash
Author: zhangdongling
Copyright(C)
Script follows here:
echo “What is your name?”
read PERSON
echo “Hello ,$PERSON”
variableName=”zhangdl”
name=dong
echo “variableName,$variableName”
echo “name,$name”
echo “1.”$0 #当前脚本的文件名
echo “2.”$1 #传递给脚本或函数的参数
echo “3.”$# #传递给脚本或函数的参数个数。
echo “4.”$* #传递给脚本或函数的所有参数。
echo “5.”@ #传递给脚本或函数的所有参数。被双引号(” “)包含时，与* 稍有不同，下面将会讲到。
echo “6.”$? #上个命令的退出状态，或函数的返回值。大部分命令执行成功会返回0，失败返回1
echo “8.\”$@\””
echo “9.\”$*\””
echo -e “pid is $$ \n”
echo “pid is $$ \n”
DATE=date
echo -e “DATE is $DATE \n”
USERS=who | wc -l
echo -e “Logged in user are $USERS \n”
UP=date;uptime
echo -e “Uptime is $UP \n”
val=expr 2 + 2
echo “Total value:$val”
a=10
b=20
val=expr a +b
echo “a + b :$val”
val=expr a -b
echo “a – b :$val”
val=expr a \*b
echo “a * b :$val”
val=expr a /b
echo “a / b :$val”
val=expr a %b
echo “a % b :$val”
if [ a ==b ]
then
echo ” a is equal to b”
fi
if [ a !=b ]
then
echo “a is not equal to b”
fi
a=10
b=20
if [ a -eqb ]
then
echo “a -eqb : a is equal to b”
else
echo “a -eqb : a is not equal to b”
fi
if [ a -neb ]
then
echo “a -neb : a is not equal to b”
else
echo “a -neb : a is equal to b”
fi
if [ a -gtb ]
then
echo “a -gtb : a is less than b”
else
echo “a -gtb : a is not less than b”
fi
if [ a -ltb ]
then
echo “a -ltb :a is less than b”
else
echo “a -ltb : a is not less than b”
fi
if [ a -geb ]
then
echo “a -geb : a is greater or equal to b”
else
echo “a -geb : a is not greater or equal to b “
fi
if [ a -leb ]
then
echo “a -leb : a is less or equal to b”
else
echo “a -leb : a is not less or equal to b”
fi
file=”/xxxx.sh”
if [ -r $file ]
then
echo “File has read access”
else
echo “File does not have read access”
fi
if [ -w $file ]
then
echo “File has write permission”
else
echo “File does not have write permission”
fi
if [ -x $file ]
then
echo “File has execute permission”
else
echo “File does not have execute permission”
fi
if [ -f $file ]
then
echo “File is an ordinary file”
else
echo “This is sepcial file”
fi
if [ -d $file ]
then
echo “File is a directory”
else
echo “This is not a direactory”
fi
if [ -s $file ]
then
echo “File size is zero”
else
echo “File size is not zero”
fi
if [ -e $file ]
then
echo “File exists”
else
echo “File does not exist”
fi
val=(a b c d e)
echo ${val[]}
echo {val[@]}
len={#val[]}
echo $len
for item in a b c d e
do
echo $item
done
function Hello(){
echo “Hello world”
}
Hello
echo $?
printf “Hello.shell \n”
printf “%d,%s\n” 1 zhangdl
str=”abcd”
echo ${#str} # 字符串长度
str=”alibaba is a great company”
echo ${str:1:4} # 提取字符串（数字表示字符串中字符对应下标）
string=”alibaba is a great company”
val=expr length $string
echo $val
