I have some files in a network storage. In Ubuntu the
storage is seen as myuser on ba-23542e.local
The question is, how do I refer to files and directories there from a script, e.g.

$dir=(this is what I do not know how to refer to)
foreach $file(readdir DIR ){....
}

Normally, files are accessed as part of a mounted filesystem. It isn't clear what you mean exactly by 'a network storage', as there are numerous network filesytems; NFS, SMB/CIFS being the most common.

You can see what filesystems are mounted on the local host, along with their respective mountpoints, by running mount with no arguments. If the network storage is not mounted, you will have to find out what network shares it exports, and then use mount, as root, with the appropriate arguments to mount the network share.

For more details:

man mount

--- rod.