Compilation Debian and Ubuntu

This how-to will guide you through compiling both qBittorrent and optionally its backend, libtorrent-rasterbar (referred to only as libtorrent for the rest of the document) from source.

Only follow this guide if you know what you are doing and this is what you really want. If you just want the latest version of qBittorrent, use our stable or unstable PPAs.

This guide is written for Debian/Ubuntu, but the process should be the same or similar for other Debian-derivative distributions.

If you run into trouble or errors at any step, check the Troubleshooting section at the bottom of the page first before posting an issue report.

Dependencies

Boost and other build dependencies

You need to install these packages in order to be able to compile qBittorrent from source.

sudo apt install build-essential pkg-config automake libtool git zlib1g-dev libssl-dev libgeoip-dev
sudo apt install libboost-dev libboost-system-dev libboost-chrono-dev libboost-random-dev

If you want, you can install the Boost libraries from source instead of installing them from the distro's repositories. This is quite easy to do, but generally does not make that much of a difference and is out of the scope of this guide.

Runtime-only dependencies

qBittorrent has a runtime-only dependency on Python 3 for its search engine functionality. Old enough versions also supported Python 2, but this has long since been deprecated.

sudo apt install python3

Qt libraries

qBittorrent uses the Qt framework as the basis for its GUI.

qBittorrent 4.0 - 4.1.x requires at least Qt 5.5.1, and qBittorrent 4.2 and later requires at least Qt 5.9.

For Debian 10, Ubuntu 18.04 LTS or later, just install Qt from the official repositories:

sudo apt install qtbase5-dev qttools5-dev libqt5svg5-dev

Note that Qt libraries in Debian 8/9 repository are too old for compiling newer qBittorrent versions, so you need to install newer Qt libraries some other way.

If you are using Ubuntu 16.04 LTS, you could add this PPA for Qt 5.9 support:

sudo add-apt-repository ppa:beineri/opt-qt597-xenial
sudo apt update
sudo apt install qt59base qt59svg qt59tools
export PATH=/opt/qt59/bin:$PATH
export PKG_CONFIG_PATH=/opt/qt59/lib/pkgconfig:$PKG_CONFIG_PATH

Alternatively, you could of course compile Qt version of your choosing from source. However, only do this if you have a very good reason to do so.

libtorrent

qBittorrent uses the libtorrent library by Arvid Norberg as the backend.

It is necessary to compile and install libtorrent before compiling qBittorrent.

It is possible to install the libtorrent development package directly from the distro's repositories:

sudo apt install libtorrent-rasterbar-dev

but the version may not be the most recent or exactly the one you want.

Alternatively, you can compile it yourself.

First, clone the libtorrent repository:

git clone https://github.com/arvidn/libtorrent.git
cd libtorrent

To compile, first choose the appropriate git and compile commands in the table below, according to the version of libtorrent you need, then run them:

libtorrent version series	qBittorrent version support	git command (example with most recent tag in series at the time of writing)	Compile commands - after running the git command, choose between using CMake (recommended) or autotools
			CMake	autotools
1.2.x	>= 4.2.0	git checkout libtorrent-1_2_5	cmake -B cmake-build-dir/release -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_STANDARD=14 cmake --build cmake-build-dir/release	./autotool.sh ./configure --disable-debug --enable-encryption CXXFLAGS="-std=c++14" make clean && make -j$(nproc)
1.1.x	>= 3.3.8 and <4.2.0 (*)	git checkout libtorrent-1_1_14	cmake -B cmake-build-dir/release -DCMAKE_BUILD_TYPE=Release cmake --build cmake-build-dir/release	./autotool.sh ./configure --disable-debug --enable-encryption make clean && make -j$(nproc)
1.0.x	<= 4.1.5	git checkout libtorrent-1_0_11

(*) Technically, the 4.2.x releases actually support the 1.1.x libtorrent series, but it is just life support and not properly tested/developed.

Finally, you can install libtorrent.

• If building with CMake:

  sudo cmake --install cmake-build-dir/release

  This generates an install_manifest.txt file in the build folder that can later be used to uninstall all installed files with sudo xargs rm < install_manifest.txt. The default installation prefix is /usr/local, as expected.

• If building with autotools:

  If you have checkinstall, the following command will generate and install a .deb package that can be tracked and managed by your package manager:

  sudo checkinstall --nodoc --backup=no --deldesc --pkgname libtorrent-rasterbar --pkgversion 1.x.x-source-compile # change the version to your liking

  Alternatively, the traditional way will do just fine (but there is no tracking of the installed files):

  sudo make install

For more information on building libtorrent, see libtorrent downloading and building.

Compiling qBittorrent (with the GUI)

First, obtain the qBittorrent source code.

Either download and extract a .tar archive from the GitHub releases page or clone the git repository:

git clone https://github.com/qbittorrent/qBittorrent

If you clone the git repository, you can use the master branch, which contains the current development version, or checkout a specific release tag:

git checkout release-4.2.5

Open the folder in a terminal window and run this to configure the build:

./configure CXXFLAGS="-std=c++14"

Once that finishes successfully, run:

 make -j$(nproc)

Finally, you can install qBittorrent:

If you have checkinstall, the following command will generate and install a .deb package that can be tracked and managed by your package manager:

sudo checkinstall --nodoc --backup=no --deldesc --pkgname qbittorrent --pkgversion 4.x.x-source-compile # change the version to your liking

Alternatively, the traditional way will do just fine:

sudo make install

That's it! qBittorrent is now installed. You should now be able to run it from the terminal or the installed shortcuts.

Compiling qBittorrent (without the GUI; aka qBittorrent-nox aka headless)

The steps are almost all the same as the GUI version except for the configure step, where you should add the --disable-gui flag to it, like so:

./configure CXXFLAGS="-std=c++14" --disable-gui

It is also recommended that you name the package qbittorrent-nox instead of qbittorrent if you use the checkinstall` method for installing.

That's it! qBittorrent headless is now installed. You should now be able to run it from the terminal with qbittorrent-nox.

Since you've disabled the graphical user interface, qBittorrent can only be controlled via its WebUI. By default, it can be accessed at http://localhost:8080 with the following credentials, after accepting the legal disclaimer that's presented the first time you run the program:

Username: admin
Password: adminadmin

Documentation about running qBittorrent without GUI is available here.

Troubleshooting

Compiling (generic)

• In the make command, the -j$(nproc) flag makes the number of build jobs equal to the number of hardware threads available. To see the actual value your system is using, run echo $(nproc) in a terminal. You could also manually specify a value like so: -j5. Higher values may make the build faster, but an eye must be kept on the memory usage.

Compiling libtorrent

• If you get a configure: error: Boost.System library not found, check if you installed all the above dependencies.

  If so, also pass the --with-boost-libdir=/usr/lib/i386-linux-gnu to the ./configure

Compiling qBittorrent

• If you're using libtorrent-rasterbar from the 0.16.x series, you also need to pass the --with-libtorrent-rasterbar0.16 option to configure. qBittorrent v3.3.x has dropped the support of libtorrent 0.16.x.
• If you want to compile with Qt4 instead of qt5, you also need to pass the --with-qt4 option to configure. qBittorrent v4.0.x has dropped support for Qt4

Running qBittorrent

If you get an error similar to qbittorrent: symbol lookup error: qbittorrent: undefined symbol: Simply run: ldconfig The following method is too complex, but if you want to know what's going on, then you can read the following method (see https://github.com/qbittorrent/qBittorrent/issues/8047):

Check if your LD_LIBRARY_PATH environment variable is set and the path /usr/local/lib is included.

Simply run env in your terminal and look for LD_LIBRARY_PATH. If so, you are good to go. If not, add the path to the variable:

export LD_LIBRARY_PATH=/usr/local/lib:${LD_LIBRARY_PATH}

Notes

• If you experience any problem with this how to, do not hesitate to contact sledgehammer999(at)qbittorrent(dot)org.