topic Re: Determine soft link directory in Operating System - HP-UX

Determine soft link directory

Amrit_1 — Thu, 19 Feb 2004 05:10:51 GMT

Location of D is /temp/
I have a soft link pointing from /A/B/C-> D.

I execute the command cd /A/B/C to login to directory D.

If I execute the dirname /A/B/C I get the o/p as /A/B. But the requirement that I need is the actually location of D.

Is there any simple way of doing this?

Re: Determine soft link directory

T G Manikandan — Thu, 19 Feb 2004 05:19:17 GMT

#ln -s /temp/d /a/b/c

# cd /a/b/c
This will now point to temp/d

Here c is link which points to /temp/d

Re: Determine soft link directory

Sanjay Kumar Suri — Thu, 19 Feb 2004 05:37:54 GMT

dirname will only extract portions of path names.

So to get what you need I afraid you have to give $dirname /temp/D only.

sks

Re: Determine soft link directory

Amrit_1 — Thu, 19 Feb 2004 05:59:14 GMT

I shall explain the problem a bit more in detail:

In the script I have a default location: /A/B/C. The user has the option of creating a directory /temp/D. If this done from the default there is a softlink pointing to the non-default.

Now the script recognizes only the default and not the non default. I need to get the softlink path so that I populate the parent directory of the softlink i.e. /temp directory.

One option is do a ll -ls -> grep "directory" -> awk NF to get the exact path of the soft link and then do dirname path

But the above is cumbersome and is round about method. Is there any faster method of accessing.

Re: Determine soft link directory

H.Merijn Brand (procura — Thu, 19 Feb 2004 06:07:32 GMT

lt09:/tmp 105 > ln -s /A/B/D D
lt09:/tmp 106 > perl -le'print readlink for @ARGV' D
/A/B/D
lt09:/tmp 107 >

This does *NOT* guarantee that the target folder does exist. It is still a symbolic link

lt09:/tmp 107 > ln -s /usr/tmp E
lt09:/tmp 108 > perl -MCwd -le'print Cwd::realpath $_ for @ARGV' D E

/var/tmp
lt09:/tmp 109 >

Enjoy, Have FUN! H.Merijn

Re: Determine soft link directory

G. Vrijhoeven — Thu, 19 Feb 2004 06:08:08 GMT

Hi Amit,

You can use pwd for dir that includes softlink dir and /bin/pwd for real location.

HTH,

Gideon

Re: Determine soft link directory

Amrit_1 — Thu, 19 Feb 2004 07:14:19 GMT

I want the implementation in unix scripting and not in perl. thanks for that info.

I tried doing a pwd on /A/B/C. The output is /A/B/C and not what I wanted i.e. the location D.

Please let me know in case I have misunderstood the explaination.

Re: Determine soft link directory

Jean-Louis Phelix — Thu, 19 Feb 2004 09:11:10 GMT

Hi,

Previous tip should work :

$ ls -l SdDD
lrwxr-xr-x 1 phelix CST 12 Feb 22 2003 SdDD -> /homeHA/SdDD
$ A=$(cd SdDD ; pwd)
$ B=$(dirname $(cd SdDD ; pwd))
$ echo $A $B
/homeHA/phelix/SdDD /homeHA/phelix
$ A=$(cd SdDD ; /usr/bin/pwd)
$ B=$(dirname $(cd SdDD ; /usr/bin/pwd))
$ echo $A $B
/homeHA/SdDD /homeHA

The only problem is if the target sym link doesn't exist ...

Regards.

Re: Determine soft link directory

Elmar P. Kolkman — Thu, 19 Feb 2004 09:19:43 GMT

Don't use the default pwd. It might use the shell buitltin, which doesn't work like you want. Use /bin/pwd to make sure you get the real working dir.