Linux - pits: IFS

1 Overview

1. When reading the contents of the file for loop, the output is broken shivers

2. Scene

1. demand
   1. Read the file
   2. Progressive

2. Source File

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3. script

   #!/bin/bash
   
   for line in `cat ${1}` 
   do 
       echo ${line}
   done 
   

4. problem

   1. The result output, this is

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      Up
      and
      Running
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      Integration
      Cookbook(3rd)
      Jenkins
      Fundamentals

3. Solution

1. the reason
   1. Before output, the need to develop ifs
2. ifs
   1. linux environment variables
   2. slightly

3. The final script
   `` `
   #! / Bin / bash

   OLD_IFS=${IFS}
   IFS=""

   for line in cat ${1}
   do
   echo ${line}
   done

   IFS=${OLD_IFS}
   ```

4. Other

1. ref
   1. SHELL read each line of the content and output files
      1. While output by, looks like you do not have this problem ...
   2. Shell usage in IFS
2. doubt
   1. IFS What the hell is this thing in the end
   2. $ {1} is a bash script parameter, if that script with awk command, need to refer to $ 1, which prevail in the end it?