How to Add External Libraries to A Cmake Install?

To add external libraries to a CMake install, you first need to include the libraries in your CMake project by specifying the library's path or using the find_library() or find_package() commands. Once the library is included in your CMake project, you can link the library to your target executable or library by using the target_link_libraries() command. Finally, when installing your project using CMake's install() command, make sure to set the destination path for the library files so that they are copied to the correct location during the install process.

How to install external libraries using cmake?

To install external libraries using CMake, you can follow these steps:

1. First, download the library source code or precompiled binaries from the library's website or repository.
2. Create a directory in your project where you will store the library files. This directory can be named "lib" or "external" for example.
3. Add the library files to the directory you created in step 2.
4. In your CMakeLists.txt file, add the following commands to include the external library:

1
2
3
4
5

# Set the path to the directory containing the library files
set(LIBRARY_PATH ${CMAKE_SOURCE_DIR}/lib)

# Include the library as a subdirectory
add_subdirectory(${LIBRARY_PATH})

1. Next, use the target_link_libraries() command to link your project with the external library. For example, if you are using the Boost library, you would add the following line to your CMakeLists.txt file:

1

target_link_libraries(your_project_name PRIVATE Boost::boost)

1. Finally, rebuild your project using CMake to include the external library. You should now be able to use the library within your project.

By following these steps, you can easily install external libraries using CMake in your project.

How to add custom commands for external libraries in cmake?

To add custom commands for external libraries in CMake, you can use the add_custom_command or add_custom_target functions. Here is an example of how to add a custom command for an external library:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13

# Add custom command to build external library
add_custom_command(
    OUTPUT mylib
    COMMAND <command_to_build_mylib>
    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/external_library
    COMMENT "Building external library"
)

# Add custom target to build external library
add_custom_target(build_mylib DEPENDS mylib)

# Add dependency on custom target to your project
add_dependencies(my_project build_mylib)

In this example, replace <command_to_build_mylib> with the actual build command for the external library. This command will be executed in the specified working directory. The add_custom_command function specifies the output file of the command, while add_custom_target creates a target for building the library. Finally, add_dependencies is used to specify that my_project depends on build_mylib.

You can include this code in your CMakeLists.txt file to add custom commands for external libraries in CMake.

What is the cmake ExternalProject module?

The cmake ExternalProject module is a module in the CMake build system that allows developers to download, build, and install external projects as part of the CMake configuration and build process. This module simplifies the handling of external dependencies in CMake projects by providing a set of functions and commands that automate the process of fetching and building external projects and integrating them into the build system. This can help simplify the management of complex project dependencies and make it easier to distribute and build CMake projects that rely on external dependencies.

How to link external libraries in a cmake project?

1. Specify the library in the CMakeLists.txt file: You need to include the library's directory and its name in your CMakeLists.txt file. For example, if you want to use a library called "mylibrary", you would add the following line to your CMakeLists.txt file:

1

target_link_libraries(your_target_name mylibrary)

1. Specify the library's include directory: If the library you are using requires header files from its include directory, you need to specify this in your CMakeLists.txt file as well. For example, if the library "mylibrary" requires header files located in "path/to/mylibrary/include", you would add the following line to your CMakeLists.txt file:

1

include_directories(path/to/mylibrary/include)

1. Run CMake to generate the build files: After making the necessary changes to your CMakeLists.txt file, you need to run CMake to generate the build files. This will ensure that your project is properly linked to the external library.
2. Build your project: Once the build files have been generated, you can build your project using your preferred build tool (e.g., make, Visual Studio, etc.). The external library should now be linked to your project and you should be able to use its functionalities in your code.

What is the role of FindPackage in cmake?

FindPackage is a module in CMake that is used to locate and configure third-party libraries or dependencies needed by the project. It searches for the specified package in the system and sets up the necessary variables and flags to use it in the project. This allows for easy integration of external libraries into the build process.