I downloaded the qt embedded demo source code recently on my linux machine. Following are the outcomes during running of the program
I compiled it statically on my x86 machine and run the application on x86 machine it runs fine. But when i took the statically compiled binary file to other machine with Atom platform It run with some missing widgets. I found that the plugins cant be ported with static compilation. Can anybody tell me is it true? If no can anybody tell me the steps for it?
I compiled it dynamically with shared libraries. Then got an executalbe on linux. I did "ldd MyAppName". It show me the shared library files it is using. But I dont know how to package these. Can anybody tell me the steps to package it?
I checked in the article on deploying qt applications on X11-linux platforms. But its not complete. Can anybody give me the detailed steps?
Any help will be appreciated......
you either have a distro, that does'nt support atom, or libraries, that are not compiled with support for it. either way - something somewhere on your system (or your qt) is not compiled for atom
The problem is that you are compiling your app, and its libraries (static or dynamic) work for x86, not for Atom. Perhaps you are able to create some sort of fat binary (lipo?) so that pieces of your app will function on x86 and Atom, but bits using the x86-only libraries will not function on Atom. (Right? That's a concise definition of your problem?)
If you have the source code for the libraries that don't run on Atom, and they're important to you, you should consider porting the code to Atom. If it's open-source code, you can contribute to the project. While you didn't give many details, my (very generic) approach to this would be to get the code on an Atom machine, write a very short test application for the library, and work out the issues.
Re #2: There's little difference between compiling an app and linking to shared libraries or dynamic libraries. On your x86 machine, if you have this code (these "plugins") compiled as dynamic libraries, it's pretty much the same as statically linking those binaries into the app. These libraries will work on x86, whether they're dynamically or statically linked.
I'm not sure if that helps very much -- if you're getting binary Qt plugins as static or dynamic libraries without source, you're out of luck. Submit a bug report. If you have source code, you can do a lot more.
I just dynamically compiled my application and ported to atom platform. I found the dependencies and ported them also and set the environment variable LD_LIBRARY_PATH on target machine to my ported shared libraries and It worked. Thanks everybody for your suggestions
Related
Basically, I wrote a program using Go and the binding for the Qt gui library (github.com/bluszcz/cutego). I moved over to the cutego fork because the original binding (github.com/therecipe/qt) isn't being maintained anymore.
My app works great but I need it to run on a machine that needs nothing installed. I'm new to Go so please forgive my ignorance. I followed the instructions to build a static executable here: (https://github.com/therecipe/qt/wiki/Deploying-Windows-to-Windows-64-bit-Static)
I get a few deprecated code warnings but the code does compile. The problem is I still end up with a dynamically compiled executable. I ran ldd using MINGW64 and I get:
Qt5Core.dll => not found
Qt5Gui.dll => not found
Qt5Widgets.dll => not found
As mentioned I am pretty new to Go, but I am also new to this kind of language as I have only developed using Python and VBA. I haven't found any clues online, I think because there's something really obvious that I am missing that everyone else knows about already.
What am I missing here? Any help would be most appreciated!
I would like my executable to be statically typed so that it can run without Qt installed.
When you use cgo, your go executable will link to shared libraries at run time depending on what C libraries the cgo code references.
If you wish to use cgo and have a stand alone executable you need to link your binary to static libraries (typically .a files). It is up to the third party module to provide such libraries, though, and qt may not provide them out of the box.
I found the problem. So with github.com/therecipe/qt you have 2 install options. You can either install the normal default way or you can install using the "static" method. You'll have problems if you do both. I ended up removing all files relative to github.com/therecipe/qt. I then installed using the static Windows x64 to Windows x64 method ONLY and followed those instructions for deploying a static executable. Worked like a charm using the instructions for MYSYS2.
I'm developing a closed source application and to do so in accordance with the LGPL I have to dynamically link Qt's libraries to my application. Does Qt do this by default or do I have to take steps to do so? If that's the case how would I go about doing it?
Qt uses dynamic linking by default.
You'll notice this immediately during deployment to a non-developer machine, because your code will not run without the Qt libraries.
If your concern is the LGPL, just be careful when compiling Qt itself. Most LGPL violations with Qt are not because of static linking (since dynamic is the default), but for compiling Qt with non-default parameters.
LGPL is not just that the library must be provided along your binaries, but also that you specify how your users can build themselves the LGPL part. If you compile Qt yourself and do not use the pre-compiled binaries from the website, you must document that part of your build configuration in your release!
As soon as you get something running on your program, start preparing a release version for a non-developer environment without Qt installed. Your program should fail as soon as you delete the DLLs that you must copy along your program (or whatever format your OS uses).
It does it by default, statically linking seems to be quite involved judging by the many questions on the site regarding it.
I come from UNIX world, I'm quite familiar with Linux, Solaris, Cygwin
and MinGW development. Recently I ported one of my
big projects (cppcms) to support MSVC,
including building static and dynamic libraries with CMake.
And I get all the time absolutely weird issues:
I had CMake build issues because Windows programming
lacks naming convention
for import and static libraries.
Now I discovered that I should use different versions of ICU (debug/release builds) according to the
actual build I do (Debug/RelWithDebInfo -- should use Debug ICU, Release release ICU) and so I should
change actual conventions for searching libraries according to debug/release mode only under MSVC.
Otherwise application just would not start giving a error on missing DLL.
I don't have any such issues under Mingw or Cygwin with GCC, Open Solaris with Sun Studio or Linux with gcc or intel compilers.
And I still have numerous wired issues and wired bugs and very strange behavior -- even some trivial things do not work
under MSVC builds, when everything works absolutely fine under Solaris/Linux/Cygwin/Mingw using GCC from 3.4 up to 4.4,
Sun Studio and Intel compilers). But not under MSVC.
To be honest, I have no idea how to deal with Last one! Because it looks like for me more like environment issues.
I know that the question is not really well defined. I think I'm quite experienced
developer and I know how to write portable and good C++ code. But using Microsoft native
tools drives me crazy with issues I just don't know how to solve.
Question: What should experienced Unix programmer with quite good base in Win32 API should know when it
starts using Genuine Microsoft Tools?
P.S.: Can someone explain why "Release With Debug Info" requires Debug version of MSVC runtime? And why there two versions of runtime exist at all?
P.P.S.: Please note I don't have issues with Win32 API, in fact Windows GCC build works absolutely fine.
Clarifications:
I'm looking for pitfalls that programmer that come from Unix world would may fall into.
For example, when moving from Linux to Solaris: make sure you compile code with -mt or
-pthreads when using multi threaded programs, linking with -lpthread is not enough.
P.S.: Can someone explain why "Release
With Debug Info" requires Debug
version of MSVC runtime?
It doesn't.
And why there
two versions of runtime exist at all?
Because the debug version does more error checking.
And I still have numerous wired issues
and wired bugs and very strange
behavior -- even some trivial things
do not work under MSVC builds,
* What am I doing wrong?
Not telling us what "wired issues and wired bugs and very strange behavior" you get.
* Where should I start?
By telling us the specific errors and problems you encounter.
* What do I miss?
Reading the documentation and learning the tools.
If your question is "What do I read to become a good Windows programmer?" then my answer is: Everything from Jeff Richter, as a start.
There is no magic bullet which will automatically make you an experienced Windows developer. Windows is a very different land compared to Unix. There are lots of quirks, weird behavior, and stuff which is just plain different. The only way to get out with your sanity intact is to tackle the transition one small problem at a time. Concentrate on a specific problem and try to understand the problem. Don't just "get it to work", but really understand what is happening. A good book about Windows programming will help.
There are huge amounts of Windows knowledge and experience accumulated in the SO community, but the only way to access it is to ask concrete questions about specific problems.
The release and debug versions of DLL's use different ways of allocating memory, that is why it is not advisable to mix release and debug versions. If you allocate something in a debug mode DLL and pass it back to the application which was compiled in release mode you may get into trouble.
In the case of your naming issues you may want to have different directories where you place your static / dll's. You can do do this in visual studio by using the configuration manager, not sure how it is under the express version.
I think you need to try and actually understand the new toolset rather than just try and squish it into your current understanding of your existing tools. For that, the best way, IMHO, is for you to try and start to use Visual Studio as Microsoft intended and then once you can build a simple project in the IDE you can move to building it using your preferred make system but do so with an understanding of how the IDE is using its make system to set things up for that build (which WILL work).
So, for example, for part 1 of your question you want to create a simple static library project and a simple dll project and look at the linker options tabs. Jump to the 'Command line' view and you'll see that a DLL uses the /OUT linker option to set the name and location of the dll file and the /LIB linker option to set the name and location of the import library. With a static library only the /OUT option is used and it indicates the name of the static lib. It's true that if you're building a static lib and a DLL from the same source and you have both the /LIB for the dll set to MyCrossPlatformCode.lib and /OUT set to MyCrossPlatformCode.dll then you may have problems if you also build a static lib with an /OUT switch of MyCrossPlatformCode.lib... Simply don't do that; either build the static libs to a different output directory (which is what OpenSSL does), or, better (IMHO), mangle the names somewhat so that you have MyCrossPlatformCode.lib/.dll and MyCrossPlatformCode_static.lib (which is what STLPort does).
Note that you might also want to mangle in (or account for) building with different versions of the Microsoft tool chain (so you might end up with stlport_vc8_x64d_static.5.1, perhaps).
An alternative approach, if you really can't face the thought of understanding your toolset, is that you could take a look at some of the popular open source systems that build quite fine on Windows and Unix systems; OpenSSL and STLPort for a start, perhaps.
Whats the best way to deploy a QT app? I've read the documentation hosted at trolltech but is it better to link with a static library or the dynamic libraries and have the user install the framework? I don't really want anyone using my app to have to download a 160mb framework just to run a simple gui frontend.
On OS X it's a good way to do a dynamic build and post-process the resulting ".app" with the macdeployqt tool which comes with Qt starting with 4.5.
This will copy the Qt frameworks used by your application into the application bundle, which results in a larger package than building a static version of your application.
Here is what you can do to make sure you get the smallest file size possibly in a dynamic build:
First off, make sure you only include the stuff you need (in the project.pro file's QT += core gui network xml lines).
Open the application bundle and remove any unneeded "Qt Plugins" from the bundle. macdeployqt automatically compies all the Qt plugins in there, which can be kind of bulky.
Make sure you are building your application in release mode. Otherwise your application might be linked against the debug libraries of the Qt4 framework, and they are really big (for instance, well over 90 MB for the debug library vs. 16 MB of a release variant without debugging symbols). This might be what happened in your case.
If you have a large application binary, you can use UPX to compress your executable file by 40-50%.
Other than that, you should use compressed disk images to deploy your application.
One of my projects uses QtGui, QtNetwork, QtCore and QtXml and the resulting bundle is about 16 MB in size.
Hope that helps.
Unfortunately you will have to include the Qt libraries you need into your own bundle, as you cannot expect your users to have Qt installed on Mac (whereas on Linux packaging systems allow you to require at least a given version of Qt.
There is a nice tool to help you with that, which is called macdeployqt. You just need to invoke it on your bundle application and it will pack the required libraries, changing the linkage of your binary to refer to them. Without it, making bundles for Mac is a real pain (it still is, but considerably less though).
http://doc.trolltech.com/4.6/deployment-mac.html#the-mac-deployment-tool
Afterwards, you can make a .dmg image as you would do with any other app. There is an option in macdeployqt that builds a basic one.
On Linux, it's better to rely on the OS's copy of Qt, as it's almost certainly installed - for OS X, almost all apps use a statically compiled library.
I have a windows screensaver that I want to recompile using the QT libraries, so that I can make available for more platforms.
I am facing problems with the deployment on Vista and XP.
I compile my screensaver statically with MT, and run the dependency checker.
The results are:
MyScreensaver.SCR needs several DLLS, QTCORE4.DLL but no MSVCx80.DLLs.
So far this is fine.
My problem is that QTCORE4.DLL in its turn, does need MSVCP80.DLL and MSVCR80.DLL
As a result my application does not run on Vista systems.
Can I build QTCORE4.DLL to be statically linked the the microsoft libraries (maybe Libcmt.lib ?) so that I do not have any dependencies in the MS CRT DLLs?
Limitations:
I do not want to have the users install the MS VC redistributables. The screensaver is only 1 MB, and it is ridiculus to ask the user to do so many changes in his computer just for a screensaver.
I do not want to use the trick to put the MS CRT dlls in the same application path with the screensaver because screensavers are installed in system32, and I want to install the minimum possible files there.
Finally, I do prefer to produce a monolithic program, rather that a bunch of DLLs
I tried a full static compilation and link of QT, but this is not allowed (if I understood correctly, by the LGPL) and also it is not recommended according to this: http://www.qtsoftware.com/developer/faqs/why-does-a-statically-built-qt-use-the-dynamic-visual-studio-runtime-libraries-do-i-need-to-deploy-those-with-my-application
After trying for solutions in various directions, it seems the most feasible one is to use the QTCore4.dll and QTGui4.dll, but having them linked statically to MSVCRT. In this way, neither my program, nor the QT DLLs will have dependencies on MSVCRT dlls.
Is there a solution to this?
( I am new to QT programming )
Thank you,
Michael
I think they are concerted that parts of your application will be compiled with /MD(d) and parts with /MT(d), but if you control everything (including 3rd party libraries) then its pretty safe to use /MT(d).
You have two options:
Those dependencies are part of Microsoft Visual C++ Runtime Library, you can deploy that library in your installshield and user silently installs it, MSVCRT library not included in Windows by default, you must deploy runtime library in your installshield and copy Qt*.dll DLLs in your application directory.
Use Static Linking of Runtime and Qt main dependencies, with this option you have one executable file, but to static compile of Qt you must have Qt commercial License for commercial use.