create symbolic links from recurisve folders?

xmrkite · 06-07-2010, 02:10 PM

Hello, I am somewhat familiar with the ln -sf command to create symbolic links.

However, can I run a command and create symbolic links for all files in a given folder and its subfolders and have all the links be in one folder?

I have a file structure such as:

\Folder\A
\Folder\B
\Folder\C

and I want to have symbolic links for all the files in the A, B, and C all in one new folder (Folder\ALL) for example.

Is this possible?

I have hundreds of folders that need to be done, so a simple 1 line command would be ideal if possible.

-Thanks

pixellany · 06-07-2010, 03:12 PM

Code:

[mherring@mystical newplay]$ for file in $(ls -R ../play/*); do ln -s $file; done

In this example, the command is run in the "newplay" directory**, which is at the same level as "play". It works fine, but the only issue is that it creates some bogus links based on the output format of "ls -R". This should be easy to fix.

**When making soft links, I always "link in" by running the ln command from inside the target folder. It avoids certain kinds of errors, and involves less typing.

smoker · 06-07-2010, 03:34 PM

Why do you want symlinks for all files in the folders ?
Surely just linking the folder is sufficient. Any actions on the symlink will be actions on the original anyway.
If you were prepared to have your ALL folder one level higher, all you'd have to do is ln -s Folder and it would contain all the folders and all the files.

Unless you want a completely flat structure with no subdirectories visible, but you will have to be careful of duplicate names.

xmrkite · 06-07-2010, 03:50 PM

"Unless you want a completely flat structure with no subdirectories visible, but you will have to be careful of duplicate names."

Yes, this is what I want. There will be no duplicate names. It's important to have the files accessible via both a single flat directory and their original directory structure.

-Thanks

colucix · 06-07-2010, 04:02 PM

What about this?

Code:

find /path/to/top/level/directory -type f -exec ln -t /path/to/link/directory -s {} \;

this will descend into folder /path/to/top/level/directory and it will create links into folder /path/to/link/directory. It is mandatory that you specify the full path of the top level directory containing all the files you want to link, otherwise the links themselves will result broken.

xmrkite · 06-07-2010, 04:34 PM

find /path/to/top/level/directory -type f -exec ln -t /path/to/link/directory -s {} \;

returns:

find: missing argument to `-exec'

Any ideas?

colucix · 06-07-2010, 04:41 PM

That's strange. The error stats there's nothing after -exec. Please, can you copy/paste the actual command line from your terminal, including the error message?

xmrkite · 06-07-2010, 05:54 PM

Here you go,

find "/media/structure/db" -type f -exec ln -t /home/usr/docs -s {} \ ;

done exactly so, all on one line, right in konsole using kubuntu 10.04

jiml8 · 06-07-2010, 06:41 PM

I'm seeing the same thing here. In fact, examples provided in man find aren't working, giving the exact same error message.

Wonder if there is a bug in find? Sure looks like it.

colucix · 06-08-2010, 03:23 AM

Even more strange. I tried it on three different systems and it works like a charm. Here is an example on Ubuntu 8.04, GNU find version 4.2.32:

Code:

$ tree -F
.
|-- ALL/
`-- folder/
    |-- A/
    |   `-- file1
    |-- B/
    |   `-- file2
    `-- C/
        `-- file3
$
$ find /home/colucix/test -type f
/home/colucix/test/folder/C/file3
/home/colucix/test/folder/A/file1
/home/colucix/test/folder/B/file2
$ find /home/colucix/test -type f -exec ln -t /home/colucix/test/ALL -s {} \;
$ ls -l ALL
total 0
lrwxrwxrwx 1 colucix users 35 2010-06-08 10:18 file1 -> /home/colucix/test/folder/A/file1
lrwxrwxrwx 1 colucix users 35 2010-06-08 10:18 file2 -> /home/colucix/test/folder/B/file2
lrwxrwxrwx 1 colucix users 35 2010-06-08 10:18 file3 -> /home/colucix/test/folder/C/file3
$

I wonder if the same error pops up if you use a different command after -exec. Anyway, which version of find do you have? If it's really a bug, maybe we have to submit it...

pwc101 · 06-08-2010, 03:55 AM

Worth a shot: try replacing the \; with a + (which should make the command faster anyway):

Code:

find /path/to/top/level/directory -type f -exec ln -t /path/to/link/directory -s {} +

colucix's way works on my Slackware 13.1 installation just fine (findutils v4.4.2).

xmrkite · 06-08-2010, 11:22 AM

find /path/to/top/level/directory -type f -exec ln -t /path/to/link/directory -s {} +

Now that worked

Thanks a ton
Strange that it did not work with the slash in there.

colucix · 06-08-2010, 11:35 AM

Quote:

Originally Posted by pwc101

Worth a shot: try replacing the \; with a +

Hi pwc101! I barely could explain the reason why this syntax works, anyway... good catch!

pwc101 · 06-08-2010, 12:11 PM

Quote:

Originally Posted by xmrkite

find /path/to/top/level/directory -type f -exec ln -t /path/to/link/directory -s {} +

Now that worked

Thanks a ton
Strange that it did not work with the slash in there.

Weird. I wasn't really expecting it to work.

The + at the end is actually faster than the \; anyway, so I tend to favour it when using find with exec: it makes find behave more like find and xargs does. Instead of a single invocation of the program being exec'ed for each file found, it collects a number of files and passes them all as arguments to a single instance of the exec'ed command, thus dramatically reducing the number of called to the exec'ed command, thereby increasing the speed of execution.

Anyway, glad it worked.