如何在Linux上识别同样内容的文件(2)

你可以在 dryrun 模式中运行这个命令 （换句话说，仅仅汇报可能会另外被做出的改动）。

$ rdfind -dryrun true ~
(DRYRUN MODE) Now scanning "/home/shark", found 12 files.
(DRYRUN MODE) Now have 12 files in total.
(DRYRUN MODE) Removed 1 files due to nonunique device and inode.
(DRYRUN MODE) Total size is 699352 bytes or 683 KiB
Removed 9 files due to unique sizes from list.2 files left.
(DRYRUN MODE) Now eliminating candidates based on first bytes:removed 0 files from list.2 files left.
(DRYRUN MODE) Now eliminating candidates based on last bytes:removed 0 files from list.2 files left.
(DRYRUN MODE) Now eliminating candidates based on sha1 checksum:removed 0 files from list.2 files left.
(DRYRUN MODE) It seems like you have 2 files that are not unique
(DRYRUN MODE) Totally, 223 KiB can be reduced.
(DRYRUN MODE) Now making results file results.txt

rdfind 命令同样提供了类似忽略空文档（-ignoreempty）和跟踪符号链接（-followsymlinks）的功能。查看 man 页面获取解释。

-ignoreempty       ignore empty files
-minsize        ignore files smaller than speficied size
-followsymlinks     follow symbolic links
-removeidentinode   remove files referring to identical inode
-checksum       identify checksum type to be used
-deterministic      determiness how to sort files
-makesymlinks       turn duplicate files into symbolic links
-makehardlinks      replace duplicate files with hard links
-makeresultsfile    create a results file in the current directory
-outputname     provide name for results file
-deleteduplicates   delete/unlink duplicate files
-sleep          set sleep time between reading files (milliseconds)
-n, -dryrun     display what would have been done, but don't do it

注意 rdfind 命令提供了 -deleteduplicates true 的设置选项以删除副本。希望这个命令语法上的小问题不会惹恼你。;-)

$ rdfind -deleteduplicates true .
...
Deleted 1 files.    <==

你将可能需要在你的系统上安装 rdfind 命令。试验它以熟悉如何使用它可能是一个好主意。

使用 fdupes 命令

fdupes 命令同样使得识别重复文件变得简单。它同时提供了大量有用的选项——例如用来迭代的 -r。在这个例子中，它像这样将重复文件分组到一起：

$ fdupes ~
/home/shs/UPGRADE
/home/shs/mytwin
 
/home/shs/lp.txt
/home/shs/lp.man
 
/home/shs/penguin.png
/home/shs/penguin0.png
/home/shs/hideme.png

这是使用迭代的一个例子，注意许多重复文件是重要的（用户的 .bashrc 和 .profile 文件）并且不应被删除。

# fdupes -r /home
/home/shark/home.html
/home/shark/index.html
 
/home/dory/.bashrc
/home/eel/.bashrc
 
/home/nemo/.profile
/home/dory/.profile
/home/shark/.profile
 
/home/nemo/tryme
/home/shs/tryme
 
/home/shs/arrow.png
/home/shs/PNGs/arrow.png
 
/home/shs/11/files_11.zip
/home/shs/ERIC/file_11.zip
 
/home/shs/penguin0.jpg
/home/shs/PNGs/penguin.jpg
/home/shs/PNGs/penguin0.jpg
 
/home/shs/Sandra_rotated.png
/home/shs/PNGs/Sandra_rotated.png

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