How to find symlink target name in script

germanyzulu · 09-19-2005, 02:39 PM

Hey,

I have a symlink
~/bin/foo/image.link
that points to
~/photos/image.jpg

I am looking for a command kind of like this:

Quote:

(From the 'ls' manpage)
-L, --dereference
when showing file information for a symbolic link, show informa-
tion for the file the link references rather than for the link
itself

Code:

$ ls -l ~/bin/foo/image.link
lrwx------  1 me me 39 Sep 19 11:47 ~/bin/foo/image.link -> ~/photos/image.jpg
$ ls -l --dereference ~/bin/foo/image.link
-rwx------  1 me me 150108 May 29  2003 ~/bin/foo/image.link

But I want the name of the target file not just info about it. The 'file' command would work fine except that I don't know how to pull out just the filename for my script, grep with a regex just lists the whole line.

Is there a command you know of/option to 'ls' ?? Or is 'sed'/'awk' something I should look into??

Thanks,

macemoneta · 09-19-2005, 03:15 PM

file somefile | awk '{print $5}'

or

ls -l somefile | awk '{print $11}'

germanyzulu · 09-19-2005, 08:41 PM

Perfect!

That's exactly what I needed.

I suppose I could have read the 'awk' man page but at the time it seemed so daunting, at least now I understand the basics of it.

Thank you!

P.S. There you go Jeremy (and macemoneta) yet another satified Linux user, at least untill I come up with another Question!

germanyzulu · 08-09-2006, 03:14 PM

Well after a long time of not thinking about this I was poking around and found the readlink command:

Code:

$readlink --help
Usage: readlink [OPTION]... FILE
Display value of a symbolic link on standard output.
[...]

The awk method does work and for more that just the question I had. But for finding the target of a symlink I think this works better. (Much simpler, easyer to read, remember what it does in a script, etc.)

Also it is contained in the coreutils package (Ubuntu) so most if not all distros will have it.

pcabrera · 08-14-2015, 10:23 AM

I know is an extremely old thread, but hey, some of these tips are still valid after years!!!

I just wanted to point out one advantage of using readlink instead of the awk solution is that readlink can follow links recursively as opposed to the awk solution.
for example, I found this thread trying to find a way to get the real java command in my system (in a script), so I ended up doing this:

Code:

readlink -f $(which java)

Which in fact has two symlinks:

Code:

which java -> /usr/bin/java
/usr/bin/java --symlink--> /etc/alternatives/java
/etc/alternatives/java --symlink--> /usr/lib/jvm/jdk1.8.0_11/bin/java