How to delete all subdirectories with a specific name

Question

I'm working on Linux and there is a folder, which contains lots of sub directories. I need to delete all of sub directories which have a same name. For example,

dir
 |---subdir1
 |---subdir2
 |     |-----subdir1
 |---file

I want to delete all of subdir1. Here is my script:

find dir -type d -name "subdir1" | while read directory ; do
    rm -rf $directory
done

However, I execute it but it seems that nothing happens.

I've tried also find dir -type d "subdir1" -delete, but still, nothing happens.

Antilles

Does find dir -type d -name "subdir1" list the folders properly? – Ornate

@Ornate Yes. It does. – Antilles

Change --delete to -delete. – Michal

@TomFenech nothing changes... – Antilles

Have your verified you have permissions to delete the directories and all their contents? – Marjoriemarjory

@Marjoriemarjory Yes. I use rm -rf dir/subdir1 to remove one of them and it works. I don't need to do sudo. – Antilles

Answer 1

If find finds the correct directories at all, these should work:

find dir -type d -name "subdir1" -exec echo rm -rf {} \; 

or

find dir -type d -name "subdir1" -exec echo rm -rf {} +

(the echo is there for verifying the command hits the files you wanted, remove it to actually run the rm and remove the directories.)

Both piping to xargs and to while read have the downside that unusual file names will cause issues. Also, find -delete will only try to remove the directories themselves, not their contents. It will fail on any non-empty directories (but you should at least get errors).

With xargs, spaces separate words by default, so even file names with spaces will not work. read can deal with spaces, but in your command it's the unquoted expansion of $tar that splits the variable on spaces.

If your filenames don't have newlines or trailing spaces, this should work, too:

find ... | while read -r x ; do rm -rf "$x" ; done

Rolanda

I can see the messages coming from echo but all of subdir1 are always there. Is it because of some format problems or some permission issues? The dir comes from Windows System and there are many unusual filenames such as names containing & – Antilles

@Yves, and if you remove the echo to actually run the rm command, do you get any errors? find -exec shouldn't mind unusual filenames, as long as no other part of the system does. – Rolanda

Answer 2

With the globstar option (enable with shopt -s globstar, requires Bash 4.0 or newer):

rm -rf **/subdir1/

The drawback of this solution as compared to using find -exec or find | xargs is that the argument list might become too long, but that would require quite a lot of directories named subdir1. On my system, ARG_MAX is 2097152.

Cenotaph

Answer 3

Using xargs:

find dir -type d  -name "subdir1" -print0 |xargs -0 rm -rf

---

Some information not directly related to the question/problem:

find|xargs or find -exec

https://www.everythingcli.org/find-exec-vs-find-xargs/

Question

Exactly what I was going to answer. But consider find -print0 and xargs -0 to account for filenames with spaces. – Kantar

It should definitely be -exec rm -rf instead of xargs (if you want to use -f at all) (Needed to vote here, sorry) – Barbaric

@Barbaric If you want to make an answer of the -exec option, go ahead (I will upvote). xargs works and is a pattern that can be reused in lots of circumstances. – Kantar

The problem is that xargs performs word splitting. – Barbaric

@Barbaric print0 I agree, about xargs or exec: danielmiessler.com/blog/linux-xargs-vs-exec ;regarding the -f I saw OP had it, so I added too. – Question

@Question Looks like the guy who wrote the xargs vs. exec blog post is missing the opportunity to use -exec ls {} +. – Barbaric

@Question although in this case we know the subdir only occurs once, so xargs' big win isn't there. However, I think it's worth sticking to one idiom whenever you're "doing something with the stuff find finds". – Kantar

No, no, no, no, ... ! xargs introduces problems but doesn't solve problems here. It can be considered wrong – Barbaric

@Kantar indeed, I always do find|xargs I knew there is -exec but never (really) used it. not because it is bad, it is easy for me to remember. :) – Question

@Barbaric if you meant the space in filename problem, I agree, print0 and -0 are required. I don't see other problems with xargs... pls tell if I am wrong, after all I didn't use exec, perhaps I missed something – Question

-exec ... + is new to me. I think it may have backward-compatibility issues, but that might not matter to some people. -print0 / -0 solves all the problems I know of with xargs. – Kantar

@Barbaric some more info about exec and xargs... you are right exec + is fast too. but I would stick to xargs, it is fast and can combine with other commands. everythingcli.org/find-exec-vs-find-xargs – Question

When -print0 is used together with xargs -0 the command is safe, that's true. (That was not used, in the moment I voted).. Anyhow why should I join by \0, pipe to an extra program, split by \0 again instead of just using -exec rm -r {} +. Afar from the performance "issues", even the less keystrokes are a benefit of -exec. – Barbaric

Anyhow, the command is not wrong any more. That's why I've removed my vote. – Barbaric

@Barbaric thank you. I put the link in answer. and learned exec + today, thanks to your comments. – Question

@Barbaric So I just found the GNU findutils changelog, and -exec ... {} + was added in 2005. That's a long time ago, but a while after I learned shell scripting :-O. Piping to xargs with \0 is slightly faster according to my simple benchmark, which makes some sense because it slightly parallelizes things, but I can agree that -exec ... {} could be seen as cleaner. – Kantar

If there are many (many) files, piping output to a separate program to handle deletions (i.e. piping to xargs -0 -n 1 or while read -r -d $'\0') has the advantage of using a separate process, which could be advantageous in multi-CPU environments. Also, it doesn't depend on a super-long command line. If you were trying to match, say, millions of files, the single command line generated by xargs alone or find ... -exec .. + would barf. – Deserved

@Deserved First, thanks for teaching me the word barf. Never heard before but it is good to know :) .. About the topic: +, or xargs will just pass as many arguments as possible to avoid too many arguments errors. Are those errors what you meant with barf? – Barbaric

PS: Imo if there are millions of files, two separate processes may be of importance: find and rm. Atm I don't see the advantage of the extra xargs process. (But I don't know how find is implemented under the hood. Also both find and rm would access the same filesystem. I don't understand the consequences of this (in Linux) completely atm but still don't see the usefulness of (good old) xargs). I personally see the advantage of xargs more when used with programs which don't support something like -exec. – Barbaric

Answer 4

From the question, it seems you've tried to use while with find. The following substitution may help you:

while IFS= read -rd '' dir; do rm -rf "$dir"; done < <(find dir -type d -name "subdir" -print0)

Loxodromic