How do I move a relative symbolic link?

Question

I have a lot of relative symbolic links that I want to move to another directory.

How can I move symbolic links (those with a relative path) while preserving the right path?

Enamor

Do you still want the links to be symbolic when moved? This has an influence on the answers you will get. – Hopscotch

And also do you still want the links to be to relative paths, or is changing them to absolute paths ok? – Clamatorial

I think this belongs on unix.stackexchange.com, though superuser.com would also work. – Sob

@fgr yes, i want to keep relative symbolic links for example ../../dir/sym will be change to ../../../dir/sym – Enamor

Answer 1

You can turn relative paths into full paths using readlink -f foo. So you would do something like:

ln -s $(readlink -f $origlink) $newlink
rm $origlink

EDIT:

I noticed that you wish to keep the paths relative. In this case, after you move the link, you can use symlinks -c to convert the absolute paths back into relative paths.

Maitland

You could also use the -r option of ln to have it create a relative link, i.e. ln -sr "$(readlink -f "$origlink")" "$newlink"; rm "$origlink". – Pipeline

Note: if the origlink does not exist, then it creates a garbage link. – Multipurpose

you should quote properly ln -rs "$(readlink -f "$origlink")" "$newlink" – Multipurpose

If you don't have the symlinks utility available, you can use the -r option of ln to convert an existing absolute symlink to a relative one. ln -srf $newlink. Or just do what @Pipeline suggests and just create a relative symlink in the first step. – Greenish

On Mac OS readlink has no option -f, so you have to brew install coreutils and use greadlink, instead. – Neisse

Answer 2

This is a perl solution that preserves relative paths:

use strictures;
use File::Copy qw(mv);
use Getopt::Long qw(GetOptions);
use Path::Class qw(file);
use autodie qw(:all GetOptions mv);

my $target;
GetOptions('target-directory=s' => \$target);
die "$0 -t target_dir symlink1 symlink2 symlink3\n" unless $target && -d $target;

for (@ARGV) {
    unless (-l $_) {
        warn "$_ is not a symlink\n";
        next;
    }
    my $newlink = file(readlink $_)->relative($target)->stringify;
    unlink $_;
    symlink $newlink, $_;
    mv $_, $target;
}

Hurlyburly

Answer 3

Use ln of course:

for i in *; do # or whatever pattern you're wanting to match
    ln -sr "$(readlink "$i")" newdir/"$i";
done;

I was surprised this works, but LN(1) must be smart enough to take note of what's going on and help you out! I even tried it with a "newdir" of ../somethingelse (which should be a no-op in the link re-writing) and .. (which will remove a .. from the link target), and it worked wonderfully.

Bossy

Answer 4

Improving on Christopher Neylan's answer:

~/bin $ cat mv_ln
#!/bin/bash
#
# inspired by https://mcmap.net/q/416287/-how-do-i-move-a-relative-symbolic-link#8523293
#          by Christopher Neylan

help() {
   echo 'usage: mv_ln src_ln dest_dir'
   echo '       mv_ln --help'
   echo
   echo '  Move the symbolic link src_ln into dest_dir while'
   echo '  keeping it relative'
   exit 1
}

[ "$1" == "--help" ] || [ ! -L "$1" ] || [ ! -d "$2" ] && help

set -e # exit on error

orig_link="$1"
orig_name=$( basename    "$orig_link" )
orig_dest=$( readlink -f "$orig_link" )
dest_dir="$2"

ln -r -s "$orig_dest" "$dest_dir/$orig_name"
rm "$orig_link"

This is also part of https://github.com/tpo/little_shell_scripts

Demerit

You forgot some quotes around the $(…) – Multipurpose

@Multipurpose - could you please give an example where the missing quote for the $( ) would have a negative/unexpected impact? – Geotaxis

In the same circumstances when missing them out from orig_link="$1". I just did some test, and I could not get it to break, may be I just put them in out of habit, because I find it easier to remember a simple rule, that avoids bugs, than a set of many rules. – Multipurpose

No need for quotes when assigning to a variable. Not a bad habit, but not necessary. – Bossy

Answer 5

One can use tar to move a folder containing relative symbolic links.

For example:

cd folder_to_move/..
tar czvf files.tgz folder_to_move
cd dest_folder/..
tar xzvf /absolute/path/to/folder_to_move/../files.tgz

# If all is fine, clean-up
rm /absolute/path/to/folder_to_move/../files.tgz
rm -rf /absolute/path/to/folder_to_move

Iorgo

Could even use a tar pipe chain to do it all in one command cd folder_to_move; tar cf - . | (cd /usr/local/dest_folder; tar xf -) – Olney

It doesn't seem to work for me. Exactly how and when are relative symlinks being rewritten by 'tar'? – Dimerous

@Dimerous See here. Normally, symbolic links are archived as such. This works for me in OSX and Linux. – Iorgo

This preserves the symlinks in the source folder "as-is" it doesn't re-write the links to accomodate any relative change to a new destination folder. So this will only work if the the src and dst folders happen to be siblings. – Celeski