shell-002 while

0

#!/bin/bashi=1while ((i<20))do        ((i=i+1))doneecho $i

1. baby_rocker.sh

baby_rocker.sh#!/bin/bashwhile [ 1=1 ]do eject eject -t done

2. repeat.sh

#!/bin/bashdeclare -i i=0declare -i MAX=1000while ((i<MAX))do        cat source.txt >> input.txt        let i++doneecho "i=$i"exit 0

3. 读文件，一次读一行，并打印

#!/bin/bashwhile read linedo        echo $linedone < input.txt

4. 循环读/etc/passwd，并分析出以：隔离的字段

#!/bin/bashIFS=':'cat /etc/passwd | {while read f1 f2 f3 f4 f5 f6 f7do        echo "username: $f1, login shell: $f7"done}

5

#!/bin/bashfoo=1while [ "$foo" -le 20 ]; do    echo "once again"    foo=$(($foo+1))doneecho "foo=$foo" exit 0

6 simplest

#!/bin/bashwhile [ 1 = 1 ]do    echo "haha"    echo "hehe"done