shell:读取文件的每一行内容并输出

写法一：
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#!/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";

原文地址：http://www.cnblogs.com/iloveyoucc/archive/2012/07/10/2585529.html