read line(逐行读取)

写法一：
----------------------------------------------------------------------------
#!/bin/bash

while read line
do
    echo $line
done < file(待读取的文件)
----------------------------------------------------------------------------

写法二：
----------------------------------------------------------------------------
#!/bin/bash

cat file(待读取的文件) | while read line
do
    echo $line
done
----------------------------------------------------------------------------

写法三：
----------------------------------------------------------------------------
for line in `cat file(待读取的文件)`
do
    echo $line
done
----------------------------------------------------------------------------

说明：
for逐行读和while逐行读是有区别的,如:
$ cat file
aaaa
bbbb
cccc dddd

$ cat file | while read line; do echo $line; done
aaaa
bbbb
cccc dddd

$ for line in $(<file); do echo $line; done
aaaa
bbbb
cccc
dddd

 

== 实践 === 

#! bin/sh

 

#$str='http://images.stylight.de/static/res200/s2870/2870657.1.jpg%0D'

#echo ${str##*fo}

#echo ${str#fo}

while read line

do

   wget -p ${line:0:59}

done < '/root/mysql/mysql.log';

 

 

转：https://www.cnblogs.com/iloveyoucc/archive/2012/07/10/2585529.html