This tutorial will cover how to install HPX using an out of source build. If you have never installed HPX before (or are doing a fresh install) you need to make sure you have the Boost library. For detailed instructions on how to install the Boost library, please take a look at the tutorial HPX Installation. After you have Boost and CMake installed you can proceed with this tutorial.
Using an Out of Source build has many advantages over an in-source build.
If you plan on modifying source code in HPX or working on an application within the HPX directory then having an out of source build is extremely helpful.
It allows you to keep your source code clean without have the build files clutter up the directory.
Also, if you plan on committing back with SVN then commands such as svn status will only show files that you have modified and not complain about the build files.
If you want to wipe out the build files completely, its a simple matter of deleting that directory.
Another nice property is that you can have multiple builds based on the same source code.
For example, if you wanted a Debug build and a Release build off of the same source code you could do that.
In the Installing HPX tutorial the user creates an in-source build.
The command that the user runs with CMake (essentially cmake .) tells CMake to build in the current directory.
To tell CMake to build in a different directory, we just change the "." to the directory we want.
We will checkout the latest version of HPX, but first we will set some environment variables and set up our directory structure.
(Note: the choosing of the names 'projects', 'build' and 'hpx_head' are completely arbitrary, if you want to put them in different places or use different names you can.)
Be sure to include these variables in your ~/.bash_profile.
$ export HPX_HEAD=$HOME/projects/hpx_head $ export HPX_BUILD=$HOME/build/hpx_head $ export HPX=$HOME/usr/local/hpx $ export PATH=$PATH:$HPX/bin $ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HPX/lib $ mkdir -p $HPX_HEAD $HPX_BUILD $HPX
Now we will checkout the latest version of HPX with SVN.
$ cd $HOME/projects $ svn checkout https://svn.cct.lsu.edu/repos/projects/parallex/trunk/hpx hpx_head
Since we have the HPX source code, we will hop over to our build directory and tell CMake to configure our build system.
$ cd $HPX_BUILD $ cmake -DCMAKE_PREFIX=$HPX -DBOOST_ROOT=$BOOST $HPX_HEAD 2> cmake.err > cmake.out $ head cmake.err && tail cmake.out $ make 2> make.err > make.out $ head make.err && tail make.out $ make install 2> make.install.err > make.install.out $ head make.install.err && make.install.out
If you have gotten this far without errors then you have sucessfully configured an out of source HPX build.
If you are interested in learning how to configure a Debug or Release version of an HPX build see Page 2.