qmake and Qt installation root directory

Swen Laur

How could I refer to Qt installation root directory available in shell as qmake -v. Is there a special qmake variable or a way to store the outcome of qmake -v in a variable.

Paul Colby

Hi @Swen-Laur,

Is there a special qmake variable or a way to store the outcome of qmake -v in a variable.

Assuming you want to store the outcome in a qmake variable (as opposed to, for example, a shell script variable), then there's a few built-in variables that probably have what you're after.

From http://doc.qt.io/qt-5/qmake-language.html#accessing-qmake-properties:

The special $$[...] operator can be used to access qmake properties

So, for example:

paul@paul-XPS-13-9343:~/tmp$ cat messages.pro 
message(Qt version: $$[QT_VERSION])
message(Qt is installed in $$[QT_INSTALL_PREFIX])
message(Qt resources can be found in the following locations:)
message(Documentation: $$[QT_INSTALL_DOCS])
message(Header files: $$[QT_INSTALL_HEADERS])
message(Libraries: $$[QT_INSTALL_LIBS])
message(Binary files (executables): $$[QT_INSTALL_BINS])
message(Plugins: $$[QT_INSTALL_PLUGINS])
message(Data files: $$[QT_INSTALL_DATA])
message(Translation files: $$[QT_INSTALL_TRANSLATIONS])
message(Settings: $$[QT_INSTALL_CONFIGURATION])
message(Examples: $$[QT_INSTALL_EXAMPLES])
paul@paul-XPS-13-9343:~/tmp$ qmake
Project MESSAGE: Qt version: 5.4.2
Project MESSAGE: Qt is installed in /usr
Project MESSAGE: Qt resources can be found in the following locations:
Project MESSAGE: Documentation: /usr/share/qt5/doc
Project MESSAGE: Header files: /usr/include/x86_64-linux-gnu/qt5
Project MESSAGE: Libraries: /usr/lib/x86_64-linux-gnu
Project MESSAGE: Binary files (executables): /usr/lib/x86_64-linux-gnu/qt5/bin
Project MESSAGE: Plugins: /usr/lib/x86_64-linux-gnu/qt5/plugins
Project MESSAGE: Data files: /usr/share/qt5
Project MESSAGE: Translation files: /usr/share/qt5/translations
Project MESSAGE: Settings: /etc/xdg
Project MESSAGE: Examples: /usr/lib/x86_64-linux-gnu/qt5/examples
paul@paul-XPS-13-9343:~/tmp$ qmake -v
QMake version 3.0
Using Qt version 5.4.2 in /usr/lib/x86_64-linux-gnu

So, at least on my installation, it looks like $$[QT_INSTALL_LIBS] is equivalent to the path given in qmake -v.

Just out of curiosity, what you want that value for?

Cheers,

pc.

Paul Colby

Please note, in my post above, all the instances of [ should be preceded by two $ chars, not one... for some reason this forum (or my browser) keeps switching between showing one and two.

For example, they should look like $ $ [QT_...] (ignoring the spaces).

If in doubt, just look at the examples in http://doc.qt.io/qt-5/qmake-language.html#accessing-qmake-properties - they're formatted correctly.

Cheers.