Re: How to restore files without deleting existing

From: Jeff Chimene (jeffchimene_at_yahoo.com)
Date: 10/04/04

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    Date: Sun, 3 Oct 2004 19:57:33 -0700 (PDT)
To: debian-user@lists.debian.org

    --- Paul E Condon <pecondon@mesanetworks.net> wrote:

    > On Sun, Oct 03, 2004 at 07:33:04PM -0700, Jeff
    > Chimene wrote:
    > >
    > > --- Rajesh Menon <prm225@cs.nyu.edu> wrote:
    > >
    > > > As far as I know, if you operate on the symlink,
    > you
    > > > are operating on
    > > > the files/dir that it points to. Unlike hard
    > links,
    > > > which are actual
    > > > copies of the link pointed to.
    > > > And if I recall right, tar's behaviour, by
    > default,
    > > > is to over-write the
    > > > destination.
    > > >
    > > > tar -xzf archive.tar.gz => it's going to create
    > > > (overwrite) a folder 'source' and dump the
    > output in
    > > > there.
    > >
    > > Thank you for the reply! I think that I clobbered
    > the
    > > symlink - i.e. the original files are in the
    > original
    > > directory. The symlink got replaced by the actual
    > > directory.
    > >
    > > Is there a way for tar to follow the symlink, or
    > am I
    > > supposed to be writing into the linked directory?
    > >
    > > Cheers,
    > > Jeff Chimene
    > >
    >
    > In my test, I used -h option only for creating .tgz
    > file
    > My untar did -not- have -h option and yet the files
    > that
    > were in the .tgz file were placed by following the
    > symlink.
    > I appears that you only need -h when you are
    > creating.
    > So, this is not likely explanation of what happened
    > to you.
    >
    > But, again, maybe Red Hat tar behaves differently.

    Hi,

    bash-2.05b$ tar --version
    tar (GNU tar) 1.13.25
    Copyright (C) 2001 Free Software Foundation, Inc.

    It's got something to do with following symlinks in a
    secure way. I found a thread that seemed to indicate
    that this behavior is more secure than previous
    symlink handling. I didn't follow the thread closely,
    but I think that's the gist of this class of behavior.

    Fortunately, I have the original files :)

    So, I will modify my restore process to write to the
    actual directory, rather than the symlink. That should
    yield the desired behavior.

    Peace,
    jec
    >
    > --
    > Paul E Condon
    > pecondon@mesanetworks.net
    >
    >
    > --
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