Linux下Shell的for循环语句

第一类：数字性循环
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for1-1.sh

#!/bin/bash  
  
for((i=1;i<=10;i++));  
do   
echo $(expr $i \* 3 + 1);  
done  

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for1-2.sh

#!/bin/bash  
  
for i in $(seq 1 10)  
do   
echo $(expr $i \* 3 + 1);  
done   

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for1-3.sh

#!/bin/bash  
  
for i in {1..10}  
do  
echo $(expr $i \* 3 + 1);  
done  

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for1-4.sh

#!/bin/bash  
  
awk 'BEGIN{for(i=1; i<=10; i++) print i}'  

第二类：字符性循环
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for2-1.sh

#!/bin/bash  
  
for i in `ls`;  
do   
echo $i is file name\! ;  
done   

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