Quick Start

First Steps

The following steps will show you how to

• download and install BASIS on your system.
• use the so-called “basisproject” command line tool to create a new empty project.
• add some example source files and edit the build configuration files to build the executable and library files.
• build and test the example project.

You need to have a Unix-like operating system such as Linux or Mac OS X installed on your machine in order to follow these steps. At the moment, there is no separate tutorial available for Windows users, but you can install CygWin as an alternative. Note, however, that BASIS can also be installed and used on Windows. Only the tools for automated software tests will not be available then. These tools are for advanced users who want to set up an automated software build and test on dedicated test machines. The testing tools are not needed for what follows.

Install BASIS

Get a copy of the source code

Clone the Git repository from GitHub as follows:

mkdir -p ~/local/src
cd ~/local/src
git clone --depth=1 https://github.com/cmake-basis/BASIS.git basis
cd basis

or Download a pre-packaged .tar.gz of the latest BASIS release and unpack it using the following command:

mkdir -p ~/local/src
cd ~/local/src
tar xzf /path/to/downloaded/cmake-basis-$version.tar.gz
cd cmake-basis-$version

Configure the build

Configure the build system using CMake 2.8.4 or a more recent version:

mkdir build && cd build
ccmake ..

• Press c to configure the project.
• Change CMAKE_INSTALL_PREFIX to ~/local.
• Set options BUILD_APPLICATIONS and BUILD_EXAMPLE to ON.
• Press g to generate the Makefiles and exit ccmake.

Build and install BASIS

CMake has generated Makefiles for GNU Make. The build is thus triggered by the make command:

make

To install BASIS after the successful build, run the following command:

make install

As a result, CMake copies the built files into the installation tree as specified by the CMAKE_INSTALL_PREFIX variable.

Set up the environment

For the following tutorial steps, set up your environment as follows. In general, however, only the change of the PATH environment variable is recommended. The other environment variables are only needed for the tutorial sessions.

Using the C or TC shell (csh/tcsh):

setenv PATH "${HOME}/local/bin:${PATH}"
setenv BASIS_EXAMPLE_DIR "${HOME}/local/share/basis/example"
setenv HELLOBASIS_RSC_DIR "${BASIS_EXAMPLE_DIR}/hellobasis"

Using the Bourne Again SHell (bash):

export PATH="${HOME}/local/bin:${PATH} "
export BASIS_EXAMPLE_DIR="${HOME}/local/share/basis/example"
export HELLOBASIS_RSC_DIR="${BASIS_EXAMPLE_DIR}/hellobasis"

Create an Example Project

Create a new and empty project as follows:

basisproject create --name HelloBasis --description "This is a BASIS project." \
             --root ~/local/src/hellobasis

The next command demonstrates that you can modify a previously created project by using the project tool again, this time with the update command.

basisproject update --root ~/local/src/hellobasis --noexample --config-settings

Here we removed the example/ subdirectory and added some configuration file used by BASIS. These options could also have been given to the initial command above instead.

See also

The guide on how to Create/Modify a Project, BasisProject.cmake, and basis_project().

Install Your Project

The build and installation of the just created empty example project is identical to the build and installation of BASIS itself:

mkdir ~/local/src/hellobasis/build
cd ~/local/src/hellobasis/build
cmake -D CMAKE_INSTALL_PREFIX=~/local ..
make

See also

The guide on how to Install any Software.

Add an Executable

Copy the source file from the example to src/:

cd ~/local/src/hellobasis
cp ${HELLOBASIS_RSC_DIR}/helloc++.cxx src/

Add the following line to src/CMakeLists.txt under the section “executable target(s)”:

basis_add_executable(helloc++.cxx)

Alternatively, you can use the implementation of this example executable in Python, Perl, BASH or MATLAB. In case of MATLAB, add also a dependency to MATLAB:

basisproject update --root ~/local/src/hellobasis --use MATLAB

Note

The basis_add_executable command, if given only a single (existing) source code file or directory as argument, uses the name of this source file without extension or the name of the directory containing all source files of the executable, respectively, as the build target name.

Change target properties

• The name of the output file is given by the OUTPUT_NAME property.
• To change this property, add the following line to the src/CMakeLists.txt file (after basis_add_executable):

basis_set_target_properties(helloc++ PROPERTIES OUTPUT_NAME "hellobasis")

If you used another source file, you need to replace “helloc++” by its name (excl. the extension).

Test the Executable

Now build the executable from the previously added source code. As the build system has been configured before using CMake, only GNU make has to be invoked. It will recognize the change of the CMakeLists.txt file and therefore reconfigure the build system before re-building the software.

cd ~/local/src/hellobasis/build
make
bin/hellobasis
How is it going?

Install the executable and test it:

make install
hellobasis
How is it going?

Note that the hellobasis executable was installed into the ~/local/bin/ directory as we set the installation root directory to ~/local using the CMAKE_INSTALL_PREFIX CMake variable. This directory should be listed in your PATH environment variable when you followed the environment set up steps at the begin of this tutorial.

Add Libraries

Next, you will add three kinds of libraries, i.e., collections of binary or script code, to your example project. We distinguish here between private, public, and script libraries. A private library is a library without public interface which is only used by other libraries and in particular executables of the project itself. A public library provides a public interface for users of your software. Therefore, the declarations of the interface given by .h files in case of C/C++ are copied to the installation directory along with the binary library file upon installation. Another kind of library is one written in a scripting language such as Python, Perl, or BASH. Such library is more commonly referred to as module.

Add a private library

Copy the files from the example to src/:

cd ~/local/src/hellobasis
cp ${HELLOBASIS_RSC_DIR}/foo.* src/

Add the following line to src/CMakeLists.txt under the section “library target(s)”:

basis_add_library(foo foo.cxx)

Add a public library

Create the subdirectory tree for the public header files declaring the public interface:

cd ~/local/src/hellobasis
basisproject update --root . --include
mkdir include/hellobasis

Copy the files from the example. The public interface is given by bar.h.

cp ${HELLOBASIS_RSC_DIR}/bar.cxx src/
cp ${HELLOBASIS_RSC_DIR}/bar.h include/hellobasis/

Add the following line to src/CMakeLists.txt under the section “library target(s)”:

basis_add_library(bar bar.cxx)

Add a scripted module

Copy the example Perl module to src/:

cd ~/local/src/hellobasis
cp ${HELLOBASIS_RSC_DIR}/FooBar.pm.in src/

Add the following line to src/CMakeLists.txt under the section “library target(s)”:

basis_add_library(FooBar.pm)

Note

Unlike C++ libraries, which are commonly build from multiple source files, libraries written in a scripting language are separate script module files. Therefore, basis_add_library can be called with only a single argument, the name of the library source file. The name of this source file will be used as build target name including the file name extension, with . replaced by _. This is to avoid name conflicts between library modules written in different languages which have the same name such as, for example, the BASIS Utilities for Python (basis.py), Perl (basis.pm), and Bash (basis.sh).

The .in suffix

• Note that some of these files have a .in file name suffix.
• This suffix can be omitted in the basis_add_library statement. It has however an impact on how this function treats this file.
• The .in suffix indicates that the file is not usable as is, but contains patterns such as @PROJECT_NAME@ which BASIS should replace during the build of the module.
• The substitution of these @*@ patterns is what we refer to as “building” script files.

Install the libraries

Now build the libraries and install them:

cd ~/local/src/hellobasis/build
make && make install

Create a Modularized Repository

BASIS is designed to integrate multiple BASIS libraries as part of a modular build system where components can be added and removed with ease. A top-level repository contains one or more modules or sub-projects, then builds those modules based on their dependencies.

See also

See Modularize a Project for usage instructions, Project Template for a reference implementation, and Project Modularization for the design.

Create a Top Level Project

export TOPLEVEL_DIR="${HOME}/local/src/collection"
basisproject create --name Collection --description "This is a BASIS TopLevel project. It demonstrates a modular project organization."  --root ${TOPLEVEL_DIR}  --toplevel

Create a Sub-project Containing a Library

Create a sub-project module similarly to how helloBasis was created earlier.

export MODA_DIR="${HOME}/local/src/collection/modules/moda"
basisproject create --name moda --description "Subproject library to be used elsewhere" --root ${MODA_DIR} --module --include
cp ${HELLOBASIS_RSC_DIR}/moda.cxx ${MODA_DIR}/src/
mkdir ${MODA_DIR}/include/moda
cp ${HELLOBASIS_RSC_DIR}/moda.h ${MODA_DIR}/include/moda/

Add the following line to ${MODA_DIR}/src/CMakeLists.txt under the section “library target(s)”:

basis_add_library(moda SHARED moda.cxx)

Create a Sub-project that uses the Library

Create a sub-project module similarly to how helloBasis was created earlier.

export MODB_DIR="${TOPLEVEL_DIR}/modules/modb"
basisproject create --name modb --description "User example subproject executable utility repository that uses the library"  --root ${MODB_DIR} --module --src --use moda
cp ${HELLOBASIS_RSC_DIR}/userprog.cxx ${MODB_DIR}/src/

Add the following line to ${MODB_DIR}/src/CMakeLists.txt under the section “executable target(s)”:

basis_add_executable(userprog.cxx)
basis_target_link_libraries(userprog moda)

Install the Projects

mkdir ${TOPLEVEL_DIR}/build
cd ${TOPLEVEL_DIR}/build
cmake -D CMAKE_INSTALL_PREFIX=~/local -D MODULE_moda=ON -D MODULE_modb=ON  ..

make install

Next Steps

Congratulations! You just finished your first BASIS tutorial.

So far you have already learned how to install BASIS on your system and set up your own software project. You have also seen how you can add your own source files to your newly created project and build the respective executables and libraries. The essentials of any software package! Thanks to BASIS, only few lines of CMake code are needed to accomplish this.

Now check out the various How-to Guides which will introduce you to even more BASIS concepts and best practices.