Bug or feature? replace symlink to directory with ln -fs does not work

[Peter Kratzer]

Dear friends,

I have encountered a problem using the command ln -sf to replace a symlink
to a directory by a symlink to a different directory.

Working in a heterogenous environment with GNU/Linux and HP-UX workstations
I found a different behaviour in this command's handling on the two
operating systems.
Contrary to the Unix behaviour (e.g. HP-UX) using this command on a
GNU/Linux system does not replace the link, but creates a new link in the
originally referenced directory.
Is this a bug, or is this behaviour intentional?

Example:

Initial situation is a directory with two (empty) subdirs and a symlink,
e.g.
drwx... dir.0
drwx... dir.1
lrwx... dirlink -> dir.0

The command "ln -sf dir.1 dirlink" gives two different results on the
different operating systems:
On GNU/Linux systems the result is:
drwx... dir.0
lrwx... dir.0/dir.1 -> dir.1
drwx... dir.1
lrwx... dirlink -> dir.0
Whereas on HP-UX systems the result is:
drwx... dir.0
drwx... dir.1
lrwx... dirlink -> dir.1

If this behaviour of the GNU utilities is not intentional I could make a
proposal of the necessary changes in ln.c (if you are interested).
If this behaviour of the GNU utilities is indeed intentional I would
suggest a related note in the documentation.

With best regards,

Peter Kratzer
IT Administrator

Philips Semiconductors GmbH         Phone: +49 8151 270-105
Petersbrunner Str. 17               Fax:   +49 8151 270-200
D-82319 Starnberg             mailto:address@hidden