How to make sure that Qt5.4.2 is installed properly

Question

I installed qt5.4 from here in Ubuntu 14.04, but when I run:

qmake -v

I always get the old version Qt5.2.1, although I think it is installed here Qt version 5.4.2 in /opt/qt54/lib. Can anyone tell me how to make sure that Qt5.4.2 is installed properly?

Thanks

Solution

You might have both versions installed, use whereis command to find about all available instance of a program:

whereis command-name

e.g:

whereis qmake

it will tell you if any other version was available, then you can use absolute path to find about its version, like:

/usr/local/bin/qmake -v

Comments

[B.rayane]

i tried to run the command you gave but it shows this error: update-alternatives: error: no alternatives for qmake

[B.rayane]

yeah i can see it now in: QMake version 3.0 Using Qt version 5.4.2 in /opt/qt54/lib but he is taken into consideration the previous one: Project MESSAGE: Qt version 5.2.1 Project ERROR: Unknown module(s) in QT: quickwidgets

[B.rayane]

How to make it consider QT5.4.2 version. Thanks

[Ravexina]

what was the output of whereis qmake ?

[B.rayane]

here it is the output : qmake: /usr/bin/qmake /usr/bin/X11/qmake /opt/qt54/bin/qmake Qt5.4.2 is in /opt/qt54/bin/qmake . kindly tell me how to make it as a default

[Ravexina]

So it's installed in /opt my suggestion is to create an alias: alias qmake="/opt/qt54/bin/qmake" you can add this line at the end of ~/.bashrc so it will be available in all your terminals.

[B.rayane]

I think it is installed here Qt version 5.4.2 in /opt/qt54/lib but how to make it as a default

[B.rayane]

I did it but still when i do qmake -v the Qt5.2.1 appears. Any other suggestions please

[Ravexina]

what is the output of /opt/qt54/bin/qmake -v ?

[B.rayane]

here it is the output Using Qt version 5.4.2 in /opt/qt54/lib but when i compile to install ardupilot it uses Qt5.2.1 how can i change it to Qt5.4.2

[Ravexina]

I'm not sure about that, you can do something like this (Not a good Idea): sudo mv /usr/bin/qmake /usr/bin/qmake-bk then sudo ln -s /opt/qt54/bin/qmake /usr/bin/qmake

[B.rayane]

Well guys, I could make Qt5.4.2 as a default by just editing default.conf in /usr/lib/x86_64-linux-gnu/qtchooser .I just added the path of Qt5.4.2. Thanks