Linux shell 脚本实例一

By 人生百味 发表于 2006-3-6 22:37:00 1. 写一个脚本，利用循环计算10的阶乘 #!/bin/sh factorial=1 for a in `seq 1 10` do        factorial=`expr $factorial /* $a` done echo "10! = $factorial" 注：上面有一行，for a in `seq 1 10`,其中seq 1 10,即列出现1到10之间所有的数字，这一行也可改为：for a in "1 2 3 4 5 6 7 8 9 10" 2. 写一个脚本，执行后，打印一行提示“Please input a number:"，要求用户输入数值，然 后打印出该数值，然后再次要求用户输入数值。直到用户输入"end"停止。 #!/bin/sh unset var while [ "$var" != "end" ] do      echo -n "please input a number: "      read var      if [ "$var" = "end" ]      then          break      fi      echo "var is $var" done 3. 写一个脚本，利用循环和continue关键字，计算100以内能被3整除的数之和 #!/bin/sh sum=0 for a in `seq 1 100` do      if [ `expr $a % 3` -ne 0 ]      then           continue      fi      echo $a      sum=`expr $sum + $a` done echo "sum = $sum" 4．一个函数，利用shift计算所有参数乘积，假设参数均为整数 #! /bin/sh result=1 while [ $# -gt 0 ] do      result=`expr $result /* $1`      shift done echo $result 5．写一个脚本，可以根据参数文件名，以正确的参数调用tar来解压缩tar.gz或tar.bz2文件。 #!/bin/sh case ${1##*.tar.} in      bz2)          tar jxvf $1          ;;      gz)          tar zxvf $1          ;;      *)          echo "wrong file type" esac 6．写一个脚本以方便用户查询rpm的相关信息。这个脚本首先提示用户选择查询依据，比如 文件名，包名，全部等。然后提示用户选择查询信息，比如包名，包里所包含的所有文件， 包的信息等。然后询问是否继续查询，是则循环刚才的过程，否则退出。 #!/bin/sh RPM=/bin/rpm option="-q" while true do        echo "what to query?"        select var in "All" "file" "package name"        do               case $var in               All)                      option=$option"a"                      break                      ;;               file)                      echo -n "please input file name: "                      option=$option"f"                      read argument                      break                      ;;               package/ name)                      echo -n "please input package name: "                      read argument                      break                      ;;               *)                      echo "please choose between 1-3"                      ;;               esac        done        echo "what do you want to know?"        select var in "location" "info" "package name"        do               case $var in               location)                      option=$option"l"                      break                      ;;               info)                      option=$option"i"                      break                      ;;               package/ name)                      break                      ;;               *)                      echo "please choose between 1-3"                      ;;               esac        done        ${RPM} $option $argument        echo "continue? [yes/no]"        read answer        if [ answer = "no" ]        then               break        fi done