[arch-general] An old, tiresome discussion: cdrtools vs cdrkit

[Xavier Chantry]

On Fri, Jan 29, 2010 at 2:10 PM, Pierre Schmitz <pierre at archlinux.de> wrote:
> Finally some interesting discussion came out of this. I am not an expert on
> linux capability support, but Thomas has posted two blog entries about this in
> Arch: http://archlinux.me/brain0/2009/07/28/using-posix-capabilities-in-linux-
> part-one/ and http://archlinux.me/brain0/2010/01/05/using-posix-capabilities-
> in-linux-part-two/
>
> In general this should work fine. The only problem is that bsdtar did not
> support storing those information (don't know if future versions support this)
> so one has to use install scripts to adjust the permissions after install.
>

When I looked into that a few months ago, it stored just fine when
creating the archive. But it did not restore them when extracting.
This got fixed in trunk, so it will probably be in the next major
release (2.8 ?).
http://code.google.com/p/libarchive/source/detail?r=1590#

xps-m1530:~> bsdtar --version
bsdtar 2.7.902a - libarchive 2.7.902a

2.7 release does not work, at least on my system.
The development version is required.

xps-m1530:~> setcap cap_net_raw=ep ./ping
unable to set CAP_SETFCAP effective capability: Operation not permitted
xps-m1530:~> sudo setcap cap_net_raw=ep ./ping
xps-m1530:~> getcap ping
ping = cap_net_raw+ep

setcap needs root.

xps-m1530:~> bsdtar cvf ping.tar.gz ping
a ping

compress normally.

xps-m1530:~>  bsdtar xvf ping.tar.gz -C /tmp
x ping
xps-m1530:~>  bsdtar xvf ping.tar.gz -C /tmp
x ping
xps-m1530:~> getcap /tmp/ping

By default, it is not restored. "p" is needed.

xps-m1530:~>  bsdtar xvpf ping.tar.gz -C /tmp
x ping: Failed to set extended attribute
bsdtar: Error exit delayed from previous errors.
xps-m1530:~> sudo bsdtar xvpf ping.tar.gz -C /tmp
x ping
xps-m1530:~> getcap /tmp/ping
/tmp/ping = cap_net_raw+ep

root is of course still needed again for setcap, and it works !