8个实用的Shell脚本分享

几个shell脚本的例子，觉得还不错。

【例子:001】判断输入为数字，字符或其他

#!/bin/bash  

read -p "Enter a number or string here:" input  

  

case $input in  

   [0-9]) echo -e "Good job, Your input is a numberic! n" ;;  

[a-zA-Z]) echo -e "Good job, Your input is a character! n" ;;  

       *) echo -e "Your input is wrong, input again!   n"  ;;  

esac

#!/bin/bash  

  

# Calculate the average of a series of numbers.  

  

SCORE="0"  

AVERAGE="0"  

SUM="0"  

NUM="0"  

  

while true; do  

  

  echo -n "Enter your score [0-100%] ('q' for quit): "; read SCORE;  

  

  if (("$SCORE" < "0"))  || (("$SCORE" > "100")); then  

    echo "Be serious.  Common, try again: "  

  elif [ "$SCORE" == "q" ]; then  

    echo "Average rating: $AVERAGE%."  

    break  

  else  

    SUM=$[$SUM + $SCORE]  

    NUM=$[$NUM + 1]  

    AVERAGE=$[$SUM / $NUM]  

  fi  

  

done  

  

echo "Exiting."

[scriptname: doit.sh]  

while (( $# > 0 ))  

do  

  echo $*  

  shift  

done   

          

/> ./doit.sh a b c d e  

a b c d e  

b c d e  

c d e  

d e  

e

# 人名列表  

# cat namelist  

Jame  

Bob  

Tom  

Jerry  

Sherry  

Alice  

John  

  

# 脚本程序  

# cat namelist.sh  

#!/bin/bash  

for name in $(cat namelist)  

do  

        echo "name= " $name  

done  

echo "The name is out of namelist file"  

  

# 输出结果  

# ./namelist.sh  

name=  Jame  

name=  Bob  

name=  Tom  

name=  Jerry  

name=  Sherry  

name=  Alice  

name=  John

【例子:005】批量测试文件是否存在

[root@host ~]# cat testfile.sh        

#!/bin/bash  

  

  

for file in test*.sh  

do  

  if [ -f $file ];then  

     echo "$file existed."  

  fi  

done  

  

[root@host ~]# ./testfile.sh  

test.sh existed.  

test1.sh existed.  

test2.sh existed.  

test3.sh existed.  

test4.sh existed.  

test5.sh existed.  

test78.sh existed.  

test_dev_null.sh existed.  

testfile.sh existed.

[root@host ~]# df -ih /tmp  

Filesystem            Inodes   IUsed   IFree IUse% Mounted on  

/dev/mapper/vg00-lvol5  

                       1000K    3.8K    997K    1% /tmp  

[root@host ~]# cat cover_disk.sh  

#!/bin/env bash  

counter=0  

max=3800  

remainder=0  

while true  

do  

    ((counter=counter+1))  

    if [ ${#counter} -gt $max ];then  

        break  

    fi  

    ((remainder=counter%1000))  

    if [ $remainder -eq 0 ];then  

        echo -e "counter=$countertdate=" $(date)  

    fi  

    mkdir -p /tmp/temp  

    cat < testfile > "/tmp/temp/myfile.$counter"  

    if [ $? -ne 0 ];then  

        echo "Failed to write file to Disk."  

        exit 1  

    fi  

done  

echo "Done!"  

[root@host ~]# ./cover_disk.sh  

counter=1000    date= Wed Sep 10 09:20:39 HKT 2014  

counter=2000    date= Wed Sep 10 09:20:48 HKT 2014  

counter=3000    date= Wed Sep 10 09:20:56 HKT 2014  

cat: write error: No space left on device  

Failed to write file to Disk.  

dd if=/dev/zero of=testfile bs=1M count=1

[root@host ~]# cat hosts.allow  

127.0.0.1  

127.0.0.2  

127.0.0.3  

127.0.0.4  

127.0.0.5  

127.0.0.6  

127.0.0.7  

127.0.0.8  

127.0.0.9  

[root@host ~]# cat readlines.sh  

#!/bin/env bash  

i=0  

while read LINE;do  

    hosts_allow[$i]=$LINE  

    ((i++))  

done < hosts.allow  

for ((i=1;i<=${#hosts_allow[@]};i++)); do  

    echo ${hosts_allow[$i]}  

done  

echo "Done"  

[root@host ~]# ./readlines.sh  

127.0.0.2  

127.0.0.3  

127.0.0.4  

127.0.0.5  

127.0.0.6  

127.0.0.7  

127.0.0.8  

127.0.0.9  

Done

[root@host ~]# cat regex.sh  

#!/bin/env sh  

#Filename: regex.sh  

regex="[A-Za-z0-9]{6}"  

if [[ $1 =~ $regex ]]  

then  

  num=$1  

  echo $num  

else  

  echo "Invalid entry"  

  exit 1  

fi  

[root@host ~]# ./regex.sh 123abc  

123abc  

  

#!/bin/env bash  

#Filename: validint.sh  

validint(){  

    ret=`echo $1 | awk '{start = match($1,/^-?[0-9]+$/);if (start == 0) print "1";else print "0"}'`  

    return $ret  

}  

  

validint $1  

  

if [ $? -ne 0 ]; then  

    echo "Wrong Entry"  

    exit 1  

else  

    echo "OK! Input number is:" $1  

fi

#!/bin/bash  

  

NOW=$(date +"%m-%d-%Y")      # 当前日期  

FILE="backup.$NOW.tar.gz"    # 备份文件  

echo "Backing up data to /tmp/backup.$NOW.tar.gz file, please wait..."  #打印信息  

tar xcvf /tmp/backup.$NOW.tar.gz /home/ /etc/ /var       # 同时备份多个文件到指定的tar压缩文件中  

echo "Done..."