qdbus and qdbusviewer crash with "No such file or directory"

[Mechanical snail]

Release: Ubuntu 13.10 (32-bit)

Package versions:
qtdbus 4:4.8.4+dfsg-0ubuntu18
qtchooser 26-3ubuntu2

Expected behavior:

The `qdbus` program runs, as does the related program `qdbusviewer`.

Actual behavior:

If I run the `qdbus` program, it always crashes:

user@host:~$ qdbus --help
qdbus: could not exec '/usr/lib/i386-linux-gnu/qt5/bin/qdbus': No such file or directory

The `qdbus` executable is actually:

user@host:~$ ls --full-time $(which qdbus)
lrwxrwxrwx 1 root root 9 2013-08-07 14:48:40.000000000 +0000 /usr/bin/qdbus -> qtchooser

Note that `/usr/lib/i386-linux-gnu/qt4/bin/qdbus` exists and seems to work if I invoke it directly.

There's a `qdbus-qt5` package in the universe repository. It was not pulled in as a dependency, but manually installing it fixes the issue. Therefore it's either a packaging error or a bug in qtchooser.

A similar thing happens if I run `qdbusviewer`:

user@host:~$ qdbusviewer
qdbusviewer: could not exec '/usr/lib/i386-linux-gnu/qt5/bin/qdbusviewer': No such file or directory

except that installing `qdbus-qt5` doesn't fix the issue.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: qdbus 4:4.8.4+dfsg-0ubuntu18
ProcVersionSignature: Ubuntu 3.11.0-13.20-generic 3.11.6
Uname: Linux 3.11.0-13-generic i686
ApportVersion: 2.12.5-0ubuntu2.1
Architecture: i386
Date: Thu Nov 14 09:34:24 2013
MarkForUpload: True
SourcePackage: qt4-x11
UpgradeStatus: Upgraded to saucy on 2013-10-23 (22 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Murz (murznn)]

I have solve this problem on Ubuntu 13.10 via command:
sudo apt-get install qt5-default qttools5-dev-tools

[David Baumann (davidbaumann)]

Same problem on Ubuntu 17.10, I think it's a bug.

[Bruce Duncan (bwduncan)]

The solution is indeed to install the qt5-default package.

Maybe this package could be added as a dependency in newer releases?

There is also perhaps an upstream bug where qtchooser could try the "other" qt version if one fails. (I had installed qdbus5, and qtchooser was trying qdbus4, which was not installed or wanted.)

[Dmitry Shachnev (mitya57)]

> Maybe this package could be added as a dependency in newer releases?

We would like to make Qt 5 default, but unfortunately this will break lots of legacy Qt 4 code. So we cannot do that soon, maybe in future...

> There is also perhaps an upstream bug where qtchooser could try the "other" qt version if one fails. (I had installed qdbus5, and qtchooser was trying qdbus4, which was not installed or wanted.)

The fallback mechanism exists (in qtchooser 52-gae5eeef and newer versions), but only for some tools: <https://code.qt.io/cgit/qtsdk/qtchooser.git/tree/src/qtchooser/main.cpp#n528>. qdbus is one of them, so if you have qdbus-qt5 installed, qtchooser will use it even if you have no qt5-default package installed. If that is not the case, please let us know your qtchooser version and the console output.

[Jacek Sandomierz (yatsek)]

Because this is top post being shown in Google search for problems with qdbusviewer and they persist also on 18.04 here is the solution:

1. Find an error message. In my case (even after installing default):

    qdbusviewer: could not exec '/usr/lib/qt5/bin/qdbusviewer': No such file or directory

2. Find in which package is file being reported as missing:

    $ apt-file search /usr/lib/qt5/bin/qdbusviewer
    qttools5-dev-tools: /usr/lib/qt5/bin/qdbusviewer

3. Install found package:

   $ sudo apt install qttools5-dev-tools

Voila!