Originally posted by: SystemAdmin

Hello people!

I have one question, does anybody know if there is anyway in UNIX to "join" directories content in just one dir?

For instance...

there are the dirs /download1 and /download2 that have a lot of subdirs and what I would like to do is to have a unique dir called download3 that I can see the content of download1 and download2 together.

I need a kind of a way to create a link from dirs download1 and download2 to download3, so any updates in the 2 first dirs would also see in download3.
Got it?

Why? Just to simplify an application that needs to look in 2 or 3 downloadX dirs for specific conent(files) that would just need to look into the download3 to see all the other dirs as well.
I run AIX 5.x.

Thanks in advance.

Narciso

Originally posted by: nagger

Symbolic links will do this for you

cd /download3
ln -s /download1/* .
ln -s /download2/* .

This assumes the filenames in download1 and 2 are unique, as you can't have a single filename (link) that refers to the two files.

Originally posted by: SystemAdmin

This will not work for the problem that Narciso is trying to solve:
"I need a kind of a way to create a link from dirs download1 and download2 to download3, so any updates in the 2 first dirs would also see in download3."

Creating a symbolic link to all of the files in another directory is a one-shot deal. It will make all the files in the source directory visible from within the target directory, but any new files added to the source directory after the ln command is run will not automatically become visible from within the target directory. In order to see any files added after the original ln command is run, you would have to re-run the original command.

Unfortunately, I do not know how to create a "join" of two directories. But it could be a handy thing to be able to do.

Originally posted by: SystemAdmin

Does he mean by this that when a new file is created in either download1 or download 2 a symlink to it is automagically created in download3? An interesting requirement to be sure. The one thing I've heard of that I think could be made to do this is "inotify".
See http://www-128.ibm.com/developerworks/linux/library/l-inotify.html for details.
Inotify is a Linux thing and I don't know if anybody's made it work on AIX.

FWIW

Jim Lane