[ILUG] How to copy some files

[kevin lyda]

On Sun, Jul 21, 2002 at 01:47:39AM +0100, Paul Jakma wrote:
> isnt this standard behaviour?? mv uses rename() which replaces the
> new path name:

why, yes.  yes it is.  i think that was my point.

> yes it does. :)
> 
> but your super-links dont is what you're saying i guess. but why? why
> would you want a symlink, bar, linking to foo, to stop linking if foo
> is changed?

uh, i wouldn't.  i was referring to the previous message which discussed
the idea of a symlink that referred to a 64 bit device id and the inode
of the file.  i gave two examples of why it wouldn't work.

> >     % ln -ss foo bar
> >     % ls -i foo
> >     111 foo
> >     % rm foo
> >     % touch floyd
> >     % ls -i floyd
> >     111 floyd
> is this an example of inode reuse? :) or do you mean that somehow 
> floyd is the new foo, (foo is dead, all hail floyd) and that bar now 
> points to floyd?

yes.  i did fail to mention that floyd might not use inode 111, but
it might.  and that was my point, having these mythical symlinks point
to the device+inode is not simple.  just like the unrm thing, it might
be possible, but hard links and soft links are the best implementations
that have survived to date on unix.  windows shortcuts are kinda weird -
they're really an application level thing.

mac aliases seem to take the idea of unix symlinks (linking by filename)
along with the concept of device+inode.  i don't know mac internals,
but i seem to remember being told it tried the former first, and then
tried the latter.  how it would deal with the 2nd example i mentioned i
dunno - i'm not certain if the mac version of inodes would suffer from
that (maybe the fs identifier for the file included the creation time
or something like that).

> how do i control this 'symlinks magically link to new files' feature?

i think it would be difficult.  it would also fail to work in numerous
situations.

kevin

-- 
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