Delete all broken symbolic links with a line?

Question

For a given folder, how can I delete all broken links within it?

I found this answer that shows how to delete one broken link, but I can't put that together in only one line. Is there a one-liner for this?

A broken symbolic is a link that points to a file/folder that doesn't exists any longer.

Straight from "man find": ` find -L /usr/ports/packages -type l -exec rm -- {} + Delete all broken symbolic links in /usr/ports/packages.` — Alexander Bird, Aug 29 '17 at 13:55

score 133 · Accepted Answer · edited May 04 '20 at 17:24

133

Here's a POSIX way of deleting all broken symbolic links in the current directory, without recursion. It works by telling find to traverse symbolic links (-L), but stopping (-prune) at every directory-or-symbolic-link-to-such.

find -L . -name . -o -type d -prune -o -type l -exec rm {} +

You can also use a shell loop. The test -L matches symbolic links, and -e matches existing files (excluding broken symlinks).

for x in * .[!.]* ..?*; do if [ -L "$x" ] && ! [ -e "$x" ]; then rm -- "$x"; fi; done

If you want to recurse into subdirectories, this technique doesn't work. With GNU find (as found on non-embedded Linux and Cygwin), you can use the -xtype predicate to detect broken symbolic links (-xtype uses the type of the target for symbolic links, and reports l for broken links).

find -xtype l -delete

POSIXly, you need to combine two tools. You can use find -type l -exec … to invoke a command on each symbolic link, and [ -e "$x" ] to test whether that link is non-broken.

find . -type l -exec sh -c 'for x; do [ -e "$x" ] || rm "$x"; done' _ {} +

The simplest solution is to use zsh. To delete all broken symbolic links in the current directory:

rm -- *(-@D)

The characters in parentheses are glob qualifiers: - to dereference symlinks, @ to match only symlinks (the combination -@ means broken symlinks only), and D to match dot files. To recurse into subdirectories, make that:

rm -- **/*(-@D)

edited May 04 '20 at 17:24

Selfish

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answered Feb 28 '14 at 15:19

Gilles 'SO- stop being evil'

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+1 for really cool zsh example, and overall answer. But same question: Why `rm` and not `unlink`? Isn't there cases where `rm` is unsafe? – fotanus Feb 28 '14 at 17:05
I don't know, I'm just asking because my tentatives used `unlink` instead. I don't know why. Maybe because it is a link? :P anyway, this is other question – fotanus Feb 28 '14 at 17:18
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was just looking at this question: http://unix.stackexchange.com/questions/34248/how-can-i-find-broken-symlinks and the cautions regarding "find -L" -- not sure if it applies, and don't have time to chase it, but someone may want to consider investigating the potential hazards here. – JustJeff Oct 07 '14 at 14:03
@JustJeff The hazard mentioned there is about difficult-to-control recursion. My use of `find -L` here prevents recursion altogether, so there is no such hazard. – Gilles 'SO- stop being evil' Oct 07 '14 at 19:10
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Another option: `find -L /path/to/check -type l -delete` (Source: http://www.commandlinefu.com/commands/view/2369/find-broken-symlinks-and-delete-them) – thdoan Nov 26 '14 at 04:10
you forgot to close the if clause in the loop option – Ohad Cohen Nov 11 '15 at 13:37
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why does this find expression not use -maxdepth to prevent recursion? – Billy left SE for Codidact Feb 11 '18 at 15:31
@billycrook I don't understand. Why do you want to use `-maxdepth`? – Gilles 'SO- stop being evil' Feb 11 '18 at 18:54
Because "In the current directory, without recursion" is the most obvious use of -maxdepth – Billy left SE for Codidact Feb 11 '18 at 19:16
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@billycrook Oh, for the first one. Because I was giving a POSIX solution and `-maxdepth` isn't in POSIX (yet, I think it's planned to be in SUSv5). – Gilles 'SO- stop being evil' Feb 11 '18 at 19:17
Your first solution doesn't delete self-referential symlinks: "Too many levels of symbolic links." – Geremia Apr 29 '20 at 23:53
@Geremia A self-referential symlink isn't broken. That solution will indeed report an error if there is a recursive symlink anywhere in the tree. – Gilles 'SO- stop being evil' Apr 30 '20 at 06:38
@Gilles'SO-stopbeingevil' How could I delete such symlinks automatedly? thanks – Geremia Apr 30 '20 at 17:16
@Geremia Please search if this has been asked already. If it hasn't, please ask a new question. It's outside the scope of this thread. – Gilles 'SO- stop being evil' Apr 30 '20 at 17:37
who else keeps coming back here? – ochitos Jan 20 '21 at 14:17
Can anyone help me generalize the proposed solutions for arbitrary paths? I am not able to do this myself. The solutions are difficult to read for beginners, some more explanations would be welcome. – normanius Nov 29 '21 at 18:42
Is this safe and POSIX? `find -L "$DIR" -wholename "$DIR" -o -type d ...` – normanius Nov 29 '21 at 18:50
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@normanius `-wholename` isn't POSIX. The command is, at least, not safe if `$DIR` contains wildcards. Apart from that, I don't understand what you mean by generalizing this “to arbitrary paths” since my answer doesn't use a specific path. You should ask a new question where you explain what you want to do. – Gilles 'SO- stop being evil' Nov 29 '21 at 21:57

score 30 · Answer 2 · answered Feb 28 '14 at 17:51

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Simple answer based on the answer you linked (for a given directory, $DIR):

find -L $DIR -maxdepth 1 -type l -delete

answered Feb 28 '14 at 17:51

sanmiguel

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I like this the best. Even the find man page seems to imply this is a solution for finding broken symlinks. – Felipe Alvarez Dec 28 '16 at 02:58
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On Mac OS (BSD `find`), @sanmiguel’s command gives an error: `find: -delete: forbidden when symlinks are followed` – Diti May 18 '17 at 11:06
Works like a charm in CentOS – Erdal G. Nov 24 '17 at 12:21
What does the type -l signify here? I thought find -L was only looking at Links, but omitting the -type l flag seems to change the results. – wheeleruniverse Oct 15 '20 at 00:53
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@JDub9 it's the difference between where to look and what to match when you look there. -L is where to look: include the contents of symlinked dirs. -type l is what to match: symlinks found when looking. – sanmiguel Oct 16 '20 at 06:07
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@jDub9 `-L` tells `find` to return info on the file a symlink points to, or the symlink itself if the file it points to does not exist. `-type l` returns only matches that are symlinks, which immediately filters out any link targets that exist, leaving only symlinks that point to a non-existent file. – sanmiguel Mar 11 '21 at 16:27
Thanks @sanmiguel. That helps! – wheeleruniverse Mar 11 '21 at 16:42

score 10 · Answer 3 · answered Jul 21 '17 at 08:42

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For MAC, do a dry run as follows:-

DIR=<some path>
find -L $DIR -maxdepth 1 -type l -print

Now, you can prune the old symlinks as follows:-

for f in `find -L $DIR -maxdepth 1 -type l`; do unlink $f; done

answered Jul 21 '17 at 08:42

saurabheights

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Great but doesn't handle directory names with a space. – Anael Mar 31 '22 at 01:19
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... which is why `"$VAR"` references in the shell should habitually be put into double quotes, except you know exactly what you're doing. – Harald Jan 22 '23 at 13:04

score 9 · Answer 4 · answered Feb 03 '17 at 10:37

9

From man find EXAMPLES:

find -L /usr/ports/packages -type l -exec rm -- {} +

Delete all broken symbolic links in /usr/ports/packages.

answered Feb 03 '17 at 10:37

MmmHmm

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`find -L /usr/ports/packages -type l -print -delete` – James McGuigan May 25 '18 at 11:36

score 8 · Answer 5 · edited May 10 '21 at 22:17

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The package symlinks is pre-installed on many distributions (including Ubuntu 16.04 & Fedora 25) and has some really useful features, one of which does precisely what you're looking for:

symlinks -d ./

    -d == delete dangling links

edited May 10 '21 at 22:17

Sridhar Sarnobat

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answered May 20 '17 at 16:36

Sam

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symlinks is not preinstalled on CentOS 7.3 or Ubuntu 14. Ubuntu 16 has kernel 4.10 which has this problem: https://groups.google.com/forum/#!topic/linux.kernel/C1Uk5cnrPgs. Of course, if you're not running an SSL server, then Ubuntu 16 is probably fine. – personal_cloud Sep 20 '17 at 22:25
Also available on Mac OS X: `sudo port install symlinks` – Sridhar Sarnobat May 10 '21 at 22:15

score 6 · Answer 6 · edited Apr 13 '17 at 12:36

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Answer based on the accepted answer to the question question "How can I find broken symlinks":

find . -type l -! -exec test -e {} \; -print | xargs rm

edited Apr 13 '17 at 12:36

Community

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answered Oct 31 '16 at 09:12

rayphi

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score 3 · Answer 7 · answered Feb 06 '18 at 11:51

You can try using rmlint.

First, change directory to the folder that contains broken symlinks, and then run the following commands to find bad symlinks pointing nowhere:

rmlint --types="badlinks"

Then rmlint will create a bash script rmlint.sh in your current directory and print a list of bad symlinks in your terminal. To delete all the bad symlinks in your current directory, you can run

./rmlint.sh

Not exactly one liner, but it is very easy to use.

score 2 · Answer 8 · answered Feb 28 '14 at 14:45

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You could use readlink to determine if a symlink is broken or not.

The following would list all the broken symlinks in a given directory (and subdirectories):

find . -type l -exec sh -c 'readlink -f "{}" 1>/dev/null || echo "{}"' -- "{}" \;

Replace echo with rm to get rid of the broken ones!

(I've redirected the output of readlink to /dev/null so as to avoid confusion; it'd list the target for the symlinks.)

answered Feb 28 '14 at 14:45

devnull

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By you nickname, I see you like redirecting to /dev/null :-) Thanks, what about `unlink`? – fotanus Feb 28 '14 at 14:49
@fotanus Why `unlink`, what's the problem with `rm`? – devnull Feb 28 '14 at 14:51
@fotanus BTW, as mentioned, in this case redirecting to `/dev/null` was purely to avoid confusion. Even if you don't, and replace `echo` with `rm`, it won't cause any sideeffect. – devnull Feb 28 '14 at 14:52
not sure.. because it is a link? :P I know it only removes the entry point, but isn't somewhat safer than rm? – fotanus Feb 28 '14 at 17:03
It seems you misunderstood what `unlink` does. It also deletes files. However `unlink`, as by POSIX, is supposed to only call the syscall `unlink` and not do anything else, while `rm` has more options and can do other things such as asking interactively confirming the delete. See [this](https://unix.stackexchange.com/questions/151951/what-is-the-difference-between-rm-and-unlink). – CherryDT Jan 15 '21 at 18:04

score 1 · Answer 9 · answered May 03 '22 at 03:46

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This answer is based on @sanmiguel's but with fd

fd -tl -L $DIR -X rm

answered May 03 '22 at 03:46

number5

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Delete all broken symbolic links with a line?

9 Answers9