I'm setting LD_LIBRARY_PATH to make newer Qt Mobility be used instead of the older one, so that the non-native apps can use it.
export LD_LIBRARY_PATH=/opt/qtm12/lib
One of the libraries is libQtSensors.so.1
but still,
/usr/lib/libQtSensors.so.1
is used instead of
/opt/qtm12/lib/libQtSensors.so.1
If I LD_PRELOAD the second library, everything is working, but I can't just preload all the qt mobility libraries, as it's not a library that is used always.
What am I doing wrong?
$echo "/opt/qtm12/lib/" > /etc/ld.so.conf.d/qtm12.txt
$ldconfig -v
Related
I have installed the latest version of Eclipse on my Windows 7 64-bit machine and the mingw compiler. In setting up a Hello World project, all goes well until I am asked for the Cross Settings what the Prefix is and the Path. The Path is obvious, it's the path to the compiler. However, I haven't the slightest idea what the Prefix is and Googling for much of the day hasn't enlightened me other than finding that a lot of other people have asked the question. Unfortunately the answers I've found appear to be for specific hardware. All I want to do is to produce an executable that will run on a Windows 32 bit or 64 bit machine.
So, what is the Prefix and how do I find what it should be?
What is probably happening here is that CDT is not locating your MingW or GCC installations.
simple - but unlikely reason - covering bases
There can be many reasons, from the simple - but unlikely at this point:
You don't have mingw installed
You don't have GCC installed
This can be tested easily by starting a shell and running gcc --version.
CDT heuristic not working
To more complicated reasons relating to your installation not being detected because the heuristic in CDT did not work on your machine. To find the correct settings, CDT will do:
Check $MINGW_HOME/bin for existence
Check <Eclipse install location>/mingw/bin for existence
Look for mingw32-gcc.exe or x86_64-w64-mingw32-gcc.exe on the PATH
Check C:\MinGW for existence
If CDT cannot find any of the above, you may lead to the situation you are in.
So, how to fix it!
Option 1
Start Eclipse from within a mingw set up shell. i.e. the one you can successfully run gcc --version from. That way Eclipse will inherit an environment that can launch GCC successfully.
Option 2
Set your environment up so that MINGW_HOME is properly defined. You can do this at the system level or within the build settings in Eclipse CDT. For example, on my machine in the build settings for the project (Right-click on the project, choose Properties, then choose C/C++ -> Environment) I have set:
MINGW_HOME to C:\MinGW
MSYS_HOME to C:\MinGW\msys\1.0
PATH to ${MINGW_HOME}\bin;${MSYS_HOME}\bin;<my normal path>
and this allows Eclipse to launch gcc as part of the build process.
NOTE The above setting were done automatically on my machine because mingw was correctly located by the heuristic.
Here is a screenshot of the build settings if it helps:
Prefix: Under the hood
To try and answer part of your original question about what Prefix is, I provide the below information. It is unlikely to be particularly helpf
Prefix, in GCC parlance, refers to the directory under which all the related GCC files are placed. With different prefixes you can have multiple GCC installed on your machine.
From the GCC FAQ:
It may be desirable to install multiple versions of the compiler on
the same system. This can be done by using different prefix paths at
configure time and a few symlinks.
The concept comes from autotools in general. Autotools is the standard GNU make system (where you do ./configure && make - simplified). The prefix is the command line option to the configure stage (--prefix) to specify where to install the tool to. GCC above uses the --prefix to allow multiple GCCs on your system.
If you really want to know more about this, read the autobook. The section on configuring covers --prefix:
‘--prefix=prefix’
The –prefix option is one of the most frequently
used. If generated ‘Makefile’s choose to observe the argument you pass
with this option, it is possible to entirely relocate the
architecture-independent portion of a package when it is installed.
For example, when installing a package like Emacs, the following
command line will cause the Emacs Lisp files to be installed in
‘/opt/gnu/share’:
$ ./configure --prefix=/opt/gnu
It is important to stress that this behavior is dependent on the generated files making use of this
information. For developers writing these files, Automake simplifies
this process a great deal. Automake is introduced in Introducing GNU
Automake.
Additionally, Mingw takes advantage of all this prefix options. Read more about that on mingw's site. But the short of it is that the main prefix for mingw is /mingw.
I am a very new to porting.
I was trying to port perl to a netbsd system. Since its a custom made build, we wont be able to run configure or make on the target netbsd system. So we are trying to cross-compile it in a host pc and copy the binary over target machine. And in order to do so, we have to make a makefile from scratch, since the format for the makefile in our build is different.
I have some basic doubts regarding this,
Firstly, In order to create a perl makefile for my custom build, what are the basic things will come. Such as ccflags, library paths etc.,?
There are some files like DynaLoader, uudmap.h, myConfig, Config.pm which gets generated while "make". How can i generate them using custum makefile.
How to set various library paths and what are they ?
The #INC, shows the perl search paths, how can i create it ?
Where exactly Perl modules get installed and when it happens?
A perl build normally involves building a stripped down version of perl named miniperl, which is then used extensively in the remainder of the process of building perl and the bundled modules.
There are two basic approaches to cross-compiling: to build miniperl for the target machine and build the modules, etc., there, or to build miniperl for the host and use it to build perl and modules for the target.
The WinCE port uses the latter approach; the rudimentary (last I knew, anyway) support for a -Dusecrosscompile switch to Configure uses the former.
I recommend you ask for advice and help on the perl5-porters mailing list: http://lists.perl.org/list/perl5-porters.html
And be prepared for hard work.
NetBSD's pkgsrc system has perl in it already and has the ability to generate binary packages that you can then install on a target machine.
I'm trying to cross-compile several libraries from OSX to iOS. I've successfully cross-compiled libjpeg and libogg.
But I can't compile libvorbis because configure insists on creating and running a small test program. This obviously fails, because it creates an armv7 binary, fails to run it, and then interprets this as missing ogg libraries.
How do you usually deal with this kind of problem? I'm tempted to hack the configure script to work around these issues, but because of this kind of failure some features may be disabled. I'm also thinking of letting configure generate a native Makefile and then convert it to use the iOS toolchain, but this seems too error prone.
Any advice?
If you are cross-compiling anything that has more dependencies than libc (glibc) it becomes much more complicated. You need to have already cross-compiled all the dependencies. And the cross-compiler toolchain and all helper build programs and scripts need to know how to find those dependencies (the cross-compiled libraries and headers).
You need to have already cross-compiled libogg (and its dependencies) and installed them into the cross-compile root directory. The headers and libraries from your build system can't be used for the host (arm7) system. They must be kept separate.
Also, if you want to have shared object libraries (*.so) and not just static libraries then there is a whole new set of complications. For example, while a cross-compiler toolchain contains a cross-compiled libc as part of the toolchain, you still need a libc for the host system. The libc that is part of the toolchain can be used for this, but the way it is structured is different than on the host system. Sometimes people copy and re-arrange the files, but often people just compile and install a new glibc for the root.
Anyways, all that to say, the two errors you are seeing are because the configure script is not able to find a cross-compiled libogg library. If you haven't already, you need to cross-compile libogg (and dependencies) and install them into your target root. Then you need to tell the configure script where your cross-compiled headers (yes, header are architecture specific) and libraries are in your target root. Usually using CFLAGS, LDFLAGS, CXXFLAGS, etc (NOT --prefix) but there may be other environment variables you need to set also to affect things like pkg-config, etc. After you have built each dependency, then you need to get the makefile to install the dependency to the root. Usually this is done with make DESTDIR=[root] install but some makefiles have their own mechanism (or no proper alternate install mechanism).
You may also need to override certain configure checks (using environment variables) that are poorly written and don't have good cross-compile defaults. These variables usually start with ac_cv_*
So the basic process is to do this for packages that you need (in dependency order):
export CFLAGS=-I[root]/usr/include LDFLAGS=-L[root]/usr/lib CXXFLAGS=-I[root]/usr/include
export ac_cv_[test1]=[yes|no] ac_cv_[test2]=[yes|no] ...
./configure --host=[arm7-blah-blah]
make
make DESTDIR=[root] install
Good luck. Once you feel comfortable with standard cross-compiling, then you will be ready to take on the real black art, the Canadian cross ;-)
I finally figured it out. I tricked configure by explicitly making it link with ogg (LDFLAGS="/usr/local/ios/lib/libogg-armv7.a" ./configure ...) and then removed the explicit reference to the library from the generated makefile.
I had developed a small program in netbeans using c++. I need to know how can i deploy/run the package on another linux system
Abdul Khaliq
I have seen your code, you probably missing XML files in the current folder... where the executable is located... paste then and then run as ./your-executable
I recommend that you use a makefile to recompile on your target machine which will ensure that your program is deployed properly.
You should use a makefile as suggested. I know that NetBeans can generate one, but it's been a while since I last did so. Maybe this can help: http://forums.netbeans.org/topic3071.html
Typically, once compiled, your executable will need several libraries. Chance is that those libraries will also be available on the target linux system.
Thus, you can simply copy your executable over to the other system. If you run ldd on your executable, you should see the list of libraries your executable is dynamically loading. Those libraries should be available on the target system as well.
In case your executable makes use of resources such as images and other binary files, you can use a resource system (e.g. Qt Resource System) and compile those binary files into your executable.
The easiest way to test is to do the copy, run
ldd yourExecutable
on the target system. It will tell you if you are missing any library. Install those libraries using the system package manager.
Of course, you also have the option to statically build all libraries into your executable. However, this is not recommended since it makes the executable too large and complicates matters.
What type of package is your netbeans compiler creating? deb,rpm? If you are moving the package to a different linux install you will need to use that distributions package type. Ubuntu - deb
Fedora/Redhat - rpm
etc...
I'm not sure how you change this in netbeans but I'm pretty sure it has the ability to. A google search could help you more.
As asked and answered here, python has a useful way of deployment without installers. Can Java do the same thing?
Is there any way to run Java's jar file without installing jre?
Is there a tool something like java2exe (win32), java2bin (linux) or java2app (mac)?
You can use Launch4j for this. Well documented and easy to use. While the resulting program still needs a JRE to run, you don't have to install the JRE on the target system. You can just copy it with your application and tell Launch4j were to find it or just wrap it up with everything else.
For creating native executables, you can use Excelsion Jet, which compiles Java to native code. We used it for a project at work, and we had to perform zero modification to the original source code (which targetted Sun's JDK).
you can embbed the JRE inside your application and create a setup or installation for your application.
You can have a look at
http://www.bearcave.com/software/java/comp_java.html
You might get it what you want.
You might want to check out how Eclipse does it - it has a native .exe that can use a local (to the installation) JRE.
You might be able to get some luck with GCJ - haven't tried it myself.
You can do it with NetBeans and a couple of tools. The result is a standalone installer that packages everything you need, so your software can run without installing JRE. It is also completely portable, because it install your software on AppData, that is, it does not need privileges to be installed. Maybe you can even configure the installation path, or you can install it on your own PC, locate the folder and copy it to distribute your software in that way.
Check the Answer I made on different post
You can use jlink to create your own customized jre which would contain only those dependencies which are needed for execution. This deployment method is really efficient. please follow **this**link for one such example.