On the command line, slim applications are usually preferred, such as the diff command and its friends. However, sometimes (human eye) pattern matching is not very good on the command line, and Gnome or other lightweight desktop environments lack intuitive diff tools. KDE provides kdiff3 and it has served well under Gnome and Mate for Debian for a long time up to and including Debian 9.13 Stretch.
However, kdiff3 is useless on Debian 10 Buster. I am not sure if this is just buggy outside KDE or even inside KDE (it probably is). However, kdiff3 is part of my toolchain, and when I work on Debian 10 Buster, I need to move the task to Debian 9.13 Stretch, or in case of continuation on Debian 10 Buster, I need to move files or whole directory structures to Debian 9.13 Stretch just for comparison.
To avoid this inconvenience, I tried to find alternatives to kdiff3 on Debian 10 Buster under Mate, but have not yet found a fully intuitive replacement. The search included meld, diffuse merge tool, vimdiff and kompare. While meld comes close, it is not very intuitive (to me). This document describes some attempts to compile and use different versions of kdiff3 on different versions of Debian.
| Debian | kdiff3 | KDE | Qt | Window System | Via | Usage |
|---|---|---|---|---|---|---|
| 11 Bullseye | 1.8.5-1 | 5.111 | package | PASS | ||
| 10 Buster | 1.8 | 5.37+ | 5.8 | source | PARTIAL OK | |
| 10 Buster | 1.7.90 | 5.54.9 | 5.11.3 | xcb | package | FAIL |
| 10 Buster | 0.9.98 | 5 | source | PASS | ||
| 9 Stretch | 0.9.98 | 4.14.26 | package | PASS |
The above window system is information provided by the application’s About dialogue.
The old version 0.9.98 has its old homepage on Sourceforge. And it seems that the feature freeze was around 2014-07-04. However, minor updates and maintenance are done from time to time (updated 3 months ago - as of 2020-12-31).
The new version (Buster) seems to be under active development and offers a port to Qt5, but lacks basic functionality (see conclusion later).
With Debian 11 Bullseye, kdiff3-qt aka KDiff3 is no longer developed and has been replaced by kdiff3.
The current package for kdiff3 is kdiff3-1.8.5 and is currently 1.5 years behind the latest source release 1.9.5 from 2022-02-23. As this is a general-purpose tool, it may be advisable to read the manual, for example to understand how to use kdiff3 with git.
The prerequisite is that you have installed all the packages listed in the section Building KDdiff3 1.8.4 on Debian 10 Buster.
This section presents two ways to compile the sources. The first will compile and install the binary into /usr/local, the second will modify the qmake project file and install the binary into /srv/kdiff3-0.9.98. For both, due to limitations of the handcrafted configure' script andqmake’, a custom prefix cannot be set on the fly from the command line.
For both locations, the following must be set up as root
export BUILD_USER=USER_ID
export BUILD_GROUP=GROUP_ID
mkdir -p /srv/{src,source,build,kdiff3-0.9.98}
chown $BUILD_USER:$BUILD_GROUP /srv/{build,source,src,kdiff3-0.9.98}The easiest way is to use a local user $BUILD_USER:$BUILD_GROUP and build the project for /usr/local:
cd /srv/src
wget https://deac-riga.dl.sourceforge.net/project/kdiff3/kdiff3/0.9.98/\
kdiff3-0.9.98.tar.gz
cd /srv/build
tar xvzf ../src/kdiff3-0.9.98.tar.gz
cd /srv/build/kdiff3-0.9.98
./configure qt4This will build kdiff3 in /srv/build/kdiff3-0.9.98/releaseQt/kdiff3 and it can be used from there. If you need to install it, do it as root:
cd releaseQt
make installThe following procedure will compile and install to /srv/kdiff3-0.9.98. Using a source and build directory is not strictly necessary, but helps to understand what is being changed during the build process.
cd /srv/src
wget https://deac-riga.dl.sourceforge.net/project/kdiff3/kdiff3/0.9.98/kdiff3-0.9.98.tar.gz
cd /srv/source
tar xvzf ../src/kdiff3-0.9.98.tar.gz
cp -a /srv/source/kdiff3-0.9.98 /srv/build/kdiff3-0.9.98
cd /srv/build/kdiff3-0.9.98
sed -i -e 's%target.path = /usr/local/bin%target.path = \
/srv/kdiff3-0.9.98/bin%' src-QT4/kdiff3.pro
sed -i -e 's%documentation.path = /usr/local/share/doc/kdiff3%\
documentation.path = /srv/kdiff3-0.9.98/doc/kdiff3%' src-QT4/kdiff3.pro
./configure qt4
cd releaseQt
make installThe binary can be installed in /srv/kdiff3-0.9.98/bin/kdiff3. The application also runs directly from its build location:
/srv/build/kdiff3-0.9.98/releaseQt/kdiff3Building KDiff3 requires the following minimum versions:
Supported compilers:
aptitude install gettext qtbase5-dev extra-cmake-modules libboost-dev \
libkf5i18n-dev libkf5coreaddons-dev libkf5iconthemes-dev libkf5parts-dev \
libkf5doctools-dev libkf5crash-dev cmake gcc build-essentialThis will download, configure and build kdiff3-1.8.4 and install it in /srv/kdiff3-1.8.4.
A clean way for cmake is to distinguish between the source, build and install directories. We will add the tar archive to src.
As root:
export BUILD_USER=USER_ID
export BUILD_GROUP=GROUP_ID
mkdir -p /srv/{build,source,src}/kdiff3-1.8.4
mkdir -p /srv/kdiff3-1.8.4/share
chown -R $BUILD_USER:$BUILD_GROUP /srv/{build,source,src}/kdiff3-1.8.4Debian 10 Buster uses an old version of cmake: 3.13.4, which doesn’t have the --install option. For the new version use cmake --install /srv/build/kdiff3-1.8.4 --prefix /srv/kdiff3-1.8.4 (untested). The following uses the old method.
As user $BUILD_USER:$BUILD_GROUP:
cd /srv/src
wget -nc https://download.kde.org/stable/kdiff3/kdiff3-1.8.4.tar.xz
cd /srv/source
tar xvJf ../src/kdiff3-1.8.4.tar.xz
cd /srv/build/kdiff3-1.8.4
cmake -DCMAKE_INSTALL_PREFIX:PATH=/srv/kdiff3-1.8.4 /srv/source/kdiff3-1.8.4
make
make installAfter installation kdiff3 can be started:
/srv/kdiff3-1.8.4/bin/kdiff3This is critique is valid for Debian 10 Buster.
Positive
Negative
kdiff3 instance dropped the window manager (mate) boundaries and made it difficult to quit or move the instance via the window manager. Quitting via the file' menu andquit’ worked. Subsequent starts dropped the window manager decorations. Even rebooting the system did not make the window manager appear again. It just shows “QMainWindow::addToolBar: invalid ‘area’ argument” when started from the command line. However, the window manager decorations are visible when executed via ‘ssh -X’ from a remote system. The above error message remains, so this is probably unrelated.diff is primarily used to understand the difference between text files, it is essential to know whether binary files are different (or not) when comparing directories.kdiff3 to KDiff3 for no reason (this was also partly observed in the old version).In view of the problems found in KDiff3 1.8.4, I would recommend using the old version kdiff3 0.9.98 on Debian 10 Buster. No guarantee. It seems to be an example of software ‘innovation’ where the application now supports Qt5 instead of Qt4 and a ‘better’ build system, but a reduction in features and in this case lacks basic features like comparing binary files or handling symbolic links. Sometimes software is like wine, the older the better.
The compilation is similar to kdiff3-1.8.4, some problems have been fixed, like the vanishing border. However, links cause the application to crash. So the previous conclusion is still valid. However, after using this version on Debian 11 Bullseye from package, it could be that the build process introduced these bugs.
| Version | Date | Notes |
|---|---|---|
| 0.1.3 | 2023-02-09 | Improve writing |
| 0.1.2 | 2022-06-20 | Shell->bash, update Debian 11, hierarchy |
| 0.1.1 | 2020-12-31 | Compilation of KDiff3-1.8.4 on Debian 10 Buster |
| 0.1.0 | 2020-07-07 | Initial release |