shell:读取文件的每一行内容并输出

转载： http://www.cnblogs.com/iloveyoucc/archive/2012/07/10/2585529.html

 

写法一：
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#!/bin/bash

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

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写法二：
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#!/bin/bash

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

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

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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