kdiff3 /

Filename Size Date modified Message
35 B
1.9 KB
17.6 KB
26.2 KB
8.6 KB
39 B
18 B
9.5 KB
4.9 KB
126 B
1.2 KB
1.5 KB

Author: Joachim Eibl  (joachim.eibl at
Copyright: (C) 2002-2009 by Joachim Eibl
KDiff3-Version: 0.9.94

KDiff3 runs best on KDE but can be built without it, depending only on Qt-libs.
These are available for Un*x, Windows, Mac.
Thus there are many setup possibilities to consider.

From version 0.9.94 on the main target platform is KDE4/Qt4.
For KDiff3 for KDE3/Qt3 use KDiff3-0.9.92 or older.


- Introduction
- License
- Requirements & Installation
  - For KDE4
  - With Qt4-libs, without KDE
    - for Linux/Un*x
    - for Windows
    - Debugging with MinGW under Windows:
    - for Mac: Building KDiff3 for Mac OSX (with Intel processor) as a universal binary
    - Creating and installing translation messages
- Additional hints


KDiff3 is a program that
- compares and merges two or three input files or directories,
- shows the differences line by line and character by character (!),
- provides an automatic merge-facility and
- an integrated editor for comfortable solving of merge-conflicts
- has support for KDE-KIO (ftp, sftp, http, fish, smb),
- has an intuitive graphical user interface,
- provides a context menu for KDE-Konqueror and Windows-Explorer,
- supports 64 bit systems. (Some build issues are discussed in here.)

Do you want help translating? Read the README in the po-subdirectory!


    GNU GENERAL PUBLIC LICENSE, Version 2, June 1991
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Steet, Fifth Floor, Boston, MA  02111-1307  USA

    For details see file "COPYING".

Exception from the GPL:
    As a special exception, the copyright holder Joachim Eibl gives permission
    to link this program with the Qt-library (commercial or open source edition)
    from Trolltech (, and he permits to distribute the resulting
    executable, without including the source code for the Qt-library in the
    source distribution.

Requirements & Installation

- for KDE4:
   From version 0.9.94 on KDiff3 supports KDE4.
   For installation on most distributions you usually also require these packages (names as on opensuse):
   - g++ (g++, version 3.4 or newer)
   - libqt4-devel (Qt4-libs, version 4.4.0 or newer)
   - libkde4-devel (KDE4 Header files and development libraries)
   - libkonq-devel (optional, needed for the kdiff3-plugin, if not installed 
                    then the contextmenu plugin for konqueror won't be built.)
   - cmake (>2.6, checks dependencies and creates the Makefiles appopriate for your system)

   Typically in a terminal (e.g. konsole) you cd into the kdiff3-directory and run these commands.

      mkdir release                                  # create sub directory
      cd release                                     # cd into that directory
      kde4-config --prefix                           # Find out your KDE4-directory and note the result
      cmake .. -DCMAKE_INSTALL_PREFIX=<KDE4-prefix>  # create Makefile, replace <KDE4-prefix> with the prior result
      make                                           # run make (compile and link)
      sudo make install                              # install as root user

   Now KDiff3 should be ready to use. Type "kdiff3" to start it.
   There should also be a entry in your KDE-start menu in "(Applications->)Development".

   For creating a debug version:
      mkdir debug
      cd debug
      kde4-config --prefix                           # Find out your KDE4-directory and note the result
      cmake .. -DCMAKE_INSTALL_PREFIX=<KDE4-prefix>  -DCMAKE_BUILD_TYPE=debugfull
      sudo make install

   The <KDE4-prefix> depends on your distribution:
   The command "kde4-config --prefix" should tell you.
   - For opensuse 11 use "/usr".

- Building KDiff3 with Qt4-libs, but without KDE
    - for Linux/Un*x
    - for Windows
    - for Mac

   The version 0.9.94 requires Qt 4.4.0 or newer (from for compilation. 

   You always need
      - kdiff3-0.9.94.tar.gz

      - for Un*x:    gcc, g++ with version >=3.4.2

      - for Windows: Qt-win-libs
                     If you have the Qt4 commercial edition, then compile with Visual Studio.NET2003 or newer.
                     If you use the Qt4 open source edition, then you'll need MinGW.
                     I verified that compilation and debugging works with these packages (probably newer ones will also work):
                     - Use MinGW-5.1.4.exe or newer to install the following or newer:
                       - gcc-core-3.4.5-20060117-1.tar.gz
                       - binutils-2.17.50-20060824-1.tar.gz
                       - gcc-g++-3.4.5-20060117-1.tar.gz
                       - mingw-runtime-3.14.tar.gz
                       - mingw32-make-3.81-2.tar.gz
                       - w32api-3.11.tar.gz
                     - gdb-6.3-2.exe (for debugging)

      - for Mac:     gcc, g++ with version >=3.4.2
      - Optional: Qt Creator IDE: Development environment optimized for Qt (

  Build-instructions (Un*x):
    - Make sure your shell-variable QTDIR is correct and that 
      your path contains the Qt4-bin-directory.
    - cd into the directory kdiff3-0.9.94/src-QT4 and type
    - qmake
    - make (or "gmake" for GNU-Make)

  Build-instructions (Windows):
    - set QTDIR=<QT4-dir>         e.g.: c:\qt\4.4.1
      set "PATH=%QTDIR%\bin;%PATH%"
    - cd into the directory kdiff3-0.9.94\src-Qt4 and type
    - qmake
    - Either "nmake" for Visual Studio or "mingw32-make" depending on what you have.

  Debugging with MinGW under Windows:
    - Qt Creator worked very good as debugger frontend too!
    - Debugging without gdb on the console:
      - The qt-win-opensource-4.4.1-mingw.exe only installs release dlls. You will have to compile the
         debug dlls yourself. Enter the qt-4.4.1-directory and run "configure -debug" and then "mingw32-make".
      - cd into the directory kdiff3-0.9.94\src-Qt4
      - edit the file "Makefile.Debug" and in the LFLAGS replace "-Wl,-subsystem,windows" with "-Wl,-subsystem,console"
         (this is necessary so that gdb can send a break signal to the running program)
      - mingw32-make debug (create a debuggable executable)
      - gdb debug\kdiff3.exe
      - At the "(gdb)"-prompt type "run" and enter to start.
      - While the program runs you can't set breakpoints, first interrupt it with Ctrl-C.
      - Use "help" to find out about how to use gdb. (Important commands: run, break, backtrace, print, quit)
         Using break with c++-methods requires to specify the parameter types too. Breakpoints in constructors might not work.

  Building KDiff3 (Qt4) for Mac OSX (with Intel processor) as a universal binary (by Michael Schmidt)
    1) Install Qt/Mac 4.x with thread support, static libraries and universal flag.
       (For Qt4 run "configure -static"; only necessary if the final binary should not require shared Qt4-libs.)
    2) cd .../kdiff3-0.9.94/src-QT4
    3a) Create a makefile for kdiff3 by executing:
    3b) optionally generate XCode-Project (for debugging purposes only) by executing:
       qmake -spec macx-xcode
    4) Execute:
    5) After the build completes copy kdiff3 from the kdiff3-0.9.94/src-QT4 directory to

  Creating and installing the translation messages
    The po directory contains translations from the KDE-translation teams.
    If you use the Qt-only-version of KDiff3, then the installation described above 
    won't install translations automatically.
    To create and install the translations:
    0) Make sure /usr/lib/qt3/bin/msg2qm exists 
       (comes with qt3-devel-tools. [Yes, really Qt3. There is no Qt4 replacement yet.])
    1) cd .../kdiff3-0.9.95/po
    2) sh create_qm_files install    (asks for a super user password)
    Just to create the files in the po directory (as needed for the windows version): 
    2) sh create_qm_files local

(End of KDiff3 with Qt4-instructions)

Additional hints

   Start from commandline:
   - Comparing 2 files:     kdiff3 file1 file2
   - Merging 2 files:       kdiff3 file1 file2 -o outputfile
   - Comparing 3 files:     kdiff3 file1 file2 file3
   - Merging 3 files:       kdiff3 file1 file2 file3 -o outputfile
        Note that file1 will be treated as base of file2 and file3.

   If all files have the same name but are in different directories, you can
   reduce typework by specifying the filename only for the first file. E.g.:
   - Comparing 3 files:     kdiff3 dir1/filename dir2 dir3
   (This also works in the open-dialog.)

   If you start without arguments, then a dialog will appear where you can
   select your files via a filebrowser.

   For more documentation, see the help-menu or the subdirectory doc.

   Have fun!