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Agenda introduce Regular Expressions Pattern Matching variable Loop cycle awk Sed skillls What is a Shell Script? A text file containing UNIX commands A text file with Read and Execute permissions A program that doesn’t need to be compiled A program that is easy to create and modify How to execute a .sh script Grant executable permission to a .sh script ,then run .sh file For example : [root@core78 home]# ls -l total 8 -rw 1 root root 149 Sep 3 09:16 checking.sh -rw 1 root root 40 Sep 14 08:10 test.py [root@core78 home]# chmod +x checking.sh [root@core78 home]# ./checking.sh 50 变量赋值和引用 同时变量名的命名须遵循如下规则： 首个字符必须为字母（a-z，A-Z） 中间不能有空格，可以使用下划线（_） 不能使用标点符号 不能使用bash里的关键字（可用help命令查看保留关键字） Shell编程中，使用变量无需事先声明，如： a=“Hellow world” echo $a b=1234 echo $a 注意： 变量设置时等号两边均不能有空格存在。 Reg express [root@core78 home]# more command.txt northwestNWCharles Main3.0.98334 westernWESharon Gray5.3.97523 southwestSWLewis Dalsass2.7.8218 southernSOSuan Chin5.1.95415 southeastSEPatricia Hemenway4.0.7417 easternEATB Savage4.4.84520 northeastNEAM Main Jr.5.1.94313 northNOMargot Weber4.5.8959 centralCTAnn Stephens5.7.94513 [root@core78 home]# grep ^n command.txt northwestNWCharles Main3.0.98334 northeastNEAM Main Jr.5.1.94313 northNOMargot Weber4.5.8959 [root@core78 home]# grep 4$ command.txt northwestNWCharles Main3.0.98334 [root@core78 home]# [root@core78 home]# grep s..th command.txt southwestSWLewis Dalsass2.7.8218 southernSOSuan Chin5.1.95415 southeastSEPatricia Hemenway4.0.7417 [root@localhost shell]# grep 3$ command.txt|wc -l 3 [root@localhost shell]# grep ^n command.txt|wc -l 3 文件比较运算 compare_file.sh #!/bin/sh if [ 1 -ne $# ] then print Error command format!\n print Right command is : compare_file file_name \n exit fi file_name=${1} if [ -e ${file_name} ]; then print ${file_name} found! \n ; else print can not found file ${file_name} \n; fi 说明： 1.命令格式： if [ 1 -ne $# ] then print Error command format!\n print Right command is : co