标签：shell
来源：《跟老男孩学Linux运维》Shell编程实战
面试题1：批量生产随机字符文件名
代码：
root@vmUbu:/home/dell/shell# vim creat_ten_htmlfile.sh
#!/bin/bash
#Date: 2017-8-25
#Author: XianWei
Path=/tmp/shelltmp
[ -d "$Path" ] || mkdir -p $Path #如果测试结果为假，就执行mkdir语句
cd $Path
for((i=0;i<10;i++)) #循环执行10次
do
namepre=`date +%s|md5sum|tr -dc "a-z"` #生成随机的10个字母
namepost=‘_oldboy.html‘ #文件名的后缀
filename=${namepre}${namepost} #字符串连接
touch $filename
echo "$filename have been created."
sleep 1
done &
wait测试
root@vmUbu:/home/dell/shell# ./creat_ten_htmlfile.sh adcaeeafbc_oldboy.html have been created. ecbdeabdaedceb_oldboy.html have been created. edffdbddee_oldboy.html have been created. beadcabbbdcbdb_oldboy.html have been created. fcaadeaedafbc_oldboy.html have been created. adddadbc_oldboy.html have been created. bcadafebdabe_oldboy.html have been created. deffebcd_oldboy.html have been created. fafbbcdcfcfecef_oldboy.html have been created. fbfdedccbcc_oldboy.html have been created. root@vmUbu:/home/dell/shell# root@vmUbu:/home/dell/shell# ll /tmp/shelltmp/ total 8 drwxr-xr-x 2 root root 4096 Aug 25 07:53 ./ drwxrwxrwt 15 root root 4096 Aug 25 08:05 ../ -rw-r--r-- 1 root root 0 Aug 25 07:53 adcaeeafbc_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 adddadbc_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 bcadafebdabe_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 beadcabbbdcbdb_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 deffebcd_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 ecbdeabdaedceb_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 edffdbddee_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 fafbbcdcfcfecef_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 fbfdedccbcc_oldboy.html -rw-r--r-- 1 root root 0 Aug 25 07:53 fcaadeaedafbc_oldboy.html
总结：
考察知识点：
1）生成随机数的方法
2）字符串连接的方法
面试题2：将面试题1中的字符串oldboy全部改为oldgirl
方法一:使用awk生成所需命令，再用bash执行
代码和测试：
root@vmUbu:/tmp/shelltmp# for i in `ls /tmp/shelltmp`;do echo $i|awk -F "_" ‘{print "mv " $0 " " $1"_oldgirl.html" }‘ |bash ;done
root@vmUbu:/tmp/shelltmp# ls
adcaeeafbc_oldgirl.html beadcabbbdcbdb_oldgirl.html edffdbddee_oldgirl.html fcaadeaedafbc_oldgirl.html
adddadbc_oldgirl.html deffebcd_oldgirl.html fafbbcdcfcfecef_oldgirl.html
bcadafebdabe_oldgirl.html ecbdeabdaedceb_oldgirl.html fbfdedccbcc_oldgirl.html
root@vmUbu:/tmp/shelltmp#方法2：使用sed替换文件名，再用mv修改文件名
代码
#!/bin/bash #Date: 2017-8-25 #Author: XianWei Path=/tmp/shelltmp [ -d "$Path" ] || exit 0 #如果测试结果为假，就执行mkdir语句 cd $Path for oldfile in `ls $Path/ |grep oldboy` do newfile=`echo $oldfile | sed s/oldboy/oldgirl/g` #生成新的文件名 mv $oldfile $newfile done & wait
面试题3：批量创建用户和密码
代码
root@vmUbu:/home/dell/shell# vim 3_create_user.sh
#!/bin/bash
#Date: 2017-8-25
#Author: XianWei
#create ten users in bulk
for((i=0;i<=10;i++))
do
username="oldboy${i}" #cannot use symbol ‘‘
password=`tr -dc "a-zA-Z0-9" </dev/urandom |head -c 8` #create 8 random charactors
#echo $username
useradd $username
echo $username:$password |chpasswd #change passwd.if os=centos,use passwd --stdin
#echo ${username}" "${password}
echo ${username}" "${password} >> passwd.txt #record the username and it‘s password
done测试
root@vmUbu:/home/dell/shell# ./3_create_user.sh root@vmUbu:/home/dell/shell# cat /etc/passwd ...... hello:x:1001:1001::/home/hello: oldboy0:x:1002:1002::/home/oldboy0: oldboy1:x:1003:1003::/home/oldboy1: oldboy2:x:1004:1004::/home/oldboy2: oldboy3:x:1005:1005::/home/oldboy3: oldboy4:x:1006:1006::/home/oldboy4: oldboy5:x:1007:1007::/home/oldboy5: oldboy6:x:1008:1008::/home/oldboy6: oldboy7:x:1009:1009::/home/oldboy7: oldboy8:x:1010:1010::/home/oldboy8: oldboy9:x:1011:1011::/home/oldboy9: oldboy10:x:1012:1012::/home/oldboy10: root@vmUbu:/home/dell/shell# #查看密码文件 root@vmUbu:/home/dell/shell# cat passwd.txt oldboy0 Je28ZqTi oldboy1 LcA5AX3u oldboy2 QF36POh2 oldboy3 5BMoklFp oldboy4 18slv8fB oldboy5 8eIVWck3 oldboy6 ZuWQcqjT oldboy7 lSeahDHM oldboy8 XvqBiFPA oldboy9 VNc8fLZC oldboy10 zdbruc2S
未完待续.......
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标签：shell
原文地址：http://237085.blog.51cto.com/227085/1959480
