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estanisgeyer
25th October 2008, 18:00
Hi friends,

You can have two different versions of the Library of QT installed on the system?
What happens is that I am developing an application with QT 4.4.2. Let's say KDE4 on another computer is based on the QT 4.4.0, I like to not give separate problems in applications?
What I did then was to copy the libraries to the same directory that I installed on my machine for development, but the problem is that the style Oxygen does not load (in Kubuntu Hardy).

Thanks,

Marcelo E. Geyer

wysota
25th October 2008, 18:09
You can have two different versions of the Library of QT installed on the system?
Yes, you can.


What happens is that I am developing an application with QT 4.4.2. Let's say KDE4 on another computer is based on the QT 4.4.0, I like to not give separate problems in applications?
Qt is binary compatible within a minor release, so your application will work with any 4.4.x Qt without recompilation.


What I did then was to copy the libraries to the same directory that I installed on my machine for development,
That's a bad idea. Use the version of Qt installed on the target system.

estanisgeyer
26th October 2008, 13:01
Hi,

I did not understand why you said it is not a good idea.
Let's assume that left the final version of QT4.5 and got my application based on this version. Already KDE is still with libraries 4.4.X. It could not share these libraries in the system because I am using the new class or functions of QT4.5. How would it? This is just one example.

Thanks for explanation.
Marcelo E. Geyer

wysota
26th October 2008, 14:51
Hi,

I did not understand why you said it is not a good idea.
Because you shouldn't move binaries between different distributions (or even distribution versions) as they might not be compatible (because of paths, for example). Using LSB tries to prevent this but I doubt you have built your Qt as LSB-compliant.


Let's assume that left the final version of QT4.5 and got my application based on this version. Already KDE is still with libraries 4.4.X. It could not share these libraries in the system because I am using the new class or functions of QT4.5. How would it? This is just one example.

I said you can share within a minor release. 4.5.x and 4.4.x are not within a minor release. In that case you need two separate bundles but they should originate from the same package source.