Using qt.conf
You can use the qt.conf
file to override paths or to specify arguments to be passed to the platform plugins.
Format and Location
The qt.conf
file is an INI text file, as described in the QSettings documentation.
QLibraryInfo will load qt.conf
from one of the following locations:
-
:/qt/etc/qt.conf
using the resource system - on macOS, in the Resource directory inside the application bundle, for example
assistant.app/Contents/Resources/qt.conf
- in the directory containing the application executable, i.e. QCoreApplication::applicationDirPath() + QDir::separator() + "qt.conf"
Overriding Paths
The qt.conf
file can be used to override the hard-coded paths that are compiled into the Qt library. These paths are accessible using the QLibraryInfo class. Without qt.conf
, the functions in QLibraryInfo return these hard-coded paths; otherwise they return the paths as specified in qt.conf
.
Without qt.conf
, the Qt libraries will use the hard-coded paths to look for plugins, translations, and so on. These paths may not exist on the target system, or they may not be accessible. Because of this, you may need qt.conf
to make the Qt libraries look elsewhere.
The file should have a Paths
group which contains the entries that correspond to each value of the QLibraryInfo::LibraryLocation enum. See the QLibraryInfo documentation for details on the meaning of the various locations.
Entry | Default Value |
---|---|
Prefix | QCoreApplication::applicationDirPath() |
Documentation | doc |
Headers | include |
Libraries | lib |
LibraryExecutables | libexec |
Binaries | bin |
Plugins | plugins |
Imports | imports |
Qml2Imports | qml |
ArchData | . |
Data | . |
Translations | translations |
Examples | examples |
Tests | tests |
Settings | . |
Absolute paths are used as specified in the qt.conf
file. All paths are relative to the Prefix
. On Windows and X11, the Prefix
is relative to the directory containing the application executable (QCoreApplication::applicationDirPath()). On macOS, the Prefix
is relative to the Contents
in the application bundle. For example, application.app/Contents/plugins/
is the default location for loading Qt plugins. Note that the plugins need to be placed in specific sub-directories under the plugins
directory (see How to Create Qt Plugins for details).
For example, a qt.conf
file could contain the following:
[Paths] Prefix = /some/path Translations = i18n
Note: The backslash character is treated as a special character in INI files (see QSettings). It is therefore recommended to use forward slashes for paths on Windows as well. Otherwise, an escape character is required:
Prefix = c:\\SomePath
Configuring Arguments to the Platform Plugins
The qt.conf
may contain a Platforms
group, whose keys are comma-delimited lists of arguments to be passed to the platform plugin. The key name is the name of the platform plugin with the first letter upper-cased followed by Arguments
.
For example:
[Platforms] WindowsArguments = fontengine=freetype
would cause the Windows platform plugin to use the FreeType font engine.
© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5.9/qt-conf.html