linux shell

#!/bin/shfor line in $(cat all_files.txt)doif [ -f "$line" ];  #A folder like /tmp/a/b is also true for -e, there is a whitespace before and after "-f".thensed 's/abc/def/g' $line >> ${line%.*}.$(date +%Y_%M_%d).fix  #elseecho "$line" >> files_not_found.txtfidone

shell读取文件的一个更加高效的方法，有两个优势：1.不用创建管道；2.不用开启cat进程。

<pre name="code" class="java">while read -r linedo        echo $linedone < all_files.txt