Can't be installed at the same time as xz-utils

[Stefano Rivera]

It uses lzma to decompress a file during installation, but if xz-utils is being installed, there is a period when neither lzma or xz-utils is available.

ProblemType: Bug
Architecture: i386
CurrentDmesg: [ 17.656061] eth0: no IPv6 routers present
Date: Wed Nov 4 12:37:18 2009
DistroRelease: Ubuntu 9.10
Lsusb: Error: command ['lsusb'] failed with exit code 1:
Package: libglu1-mesa (not installed)
PciDisplay:
 00:02.0 VGA compatible controller [0300]: Technical Corp. Device [1234:1111]
  Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
  Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
  Region 0: Memory at e0000000 (32-bit, prefetchable) [size=16M]
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.31-14-generic-pae root=UUID=d6da6bdf-29d7-428d-85ec-f94754026ea5 ro quiet splash
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_ZA.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic-pae
RelatedPackageVersions:
 xserver-xorg 1:7.4+3ubuntu7
 libgl1-mesa-glx N/A
 libdrm2 2.4.14-1ubuntu1
 xserver-xorg-video-intel 2:2.9.0-1ubuntu2
 xserver-xorg-video-ati 1:6.12.99+git20090929.7968e1fb-0ubuntu1
SourcePackage: mesa
Uname: Linux 2.6.31-14-generic-pae i686
XorgConf: Error: [Errno 2] No such file or directory: '/etc/X11/xorg.conf'
XorgLog: Error: [Errno 2] No such file or directory: '/var/log/Xorg.0.log'
XorgLogOld: Error: [Errno 2] No such file or directory: '/var/log/Xorg.0.log.old'
Xrandr: Error: command ['xrandr', '--verbose'] failed with exit code 1: Can't open display
dmi.bios.date: 01/01/2007
dmi.bios.vendor: QEMU
dmi.bios.version: QEMU
dmi.chassis.type: 1
dmi.modalias: dmi:bvnQEMU:bvrQEMU:bd01/01/2007:svn:pn:pvr:cvn:ct1:cvr:
fglrx: Not loaded
glxinfo: Error: [Errno 2] No such file or directory
setxkbmap: Error: command ['setxkbmap', '-print'] failed with exit code 255: Cannot open display "default display"
system:
 distro: Ubuntu
 architecture: i686kernel: 2.6.31-14-generic-pae
xdpyinfo: Error: command ['xdpyinfo'] failed with exit code 1: xdpyinfo: unable to open display "".
xkbcomp:
 Error: command ['xkbcomp', ':0', '-w0', '-'] failed with exit code 1: Error: Cannot open display ":0"
                   Exiting

[Jonathan Nieder (jrnieder)]

Since lzma is an essential command, other packages do not wait for the package providing it to be unpacked or configured to use it. So just as you wrote, while xz-utils is replacing lzma it does not work. For this reason, apt-get does not even allow such an installation (but aptitude does).

The long-term fix is to stop making dpkg depend on lzma, after which lzma will no longer be essential. See <http://bugs.debian.org/547802>.

In the short term, xz-utils should stop providing the lzma command, so xz-utils can be installed without removing lzma. This is what the Debian package does. Please sync when you get a chance --- the version in testing addresses several serious bugs from the experimental version you are using.

[Timo Aaltonen (tjaalton)]

xz-utils in lucid now includes the fix.

[Colin Watson (cjwatson)]

dpkg will no longer depend on lzma in maverick, once this change has built:

dpkg (1.15.7.2ubuntu1) maverick; urgency=low

  * Resynchronise with Debian. Remaining changes:
[...]

 -- Colin Watson <email address hidden> Thu, 20 May 2010 15:41:52 +0100

[...]

dpkg (1.15.6) experimental; urgency=low

[...]
  [ Guillem Jover ]
[...]
  * Add support for xz compressed data.tar member of binary packages. Add
    xz-utils to dpkg's Pre-Depends. Closes: #542160
    Thanks to Jonathan Nieder for the initial patch.
  * Use xz command to handle lzma compressed files in dpkg and dpkg-dev.
    This removes the lzma package from both dpkg and dpkg-dev dependencies.
[...]

 -- Guillem Jover <email address hidden> Fri, 12 Mar 2010 00:15:31 +0100