How to Properly Check For A Function Using Cmake?

To properly check for a function using CMake, you can use the CHECK_FUNCTION_EXISTS() macro provided by CMake. This macro takes the name of the function you want to check for as its argument, and sets a CMake variable to TRUE if the function exists in the current CMake environment. You can then use this variable in your CMake script to conditionally include or exclude certain code or libraries based on whether the function is available. By using this macro, you can ensure that your CMake scripts are robust and can handle different function availability scenarios across different platforms and environments.

How to use conditionals in CMakeLists.txt file?

Conditionals in a CMakeLists.txt file can be used to execute certain commands or set certain variables based on conditions such as the operating system, architecture, or compiler being used. Here is an example of how to use conditionals in a CMakeLists.txt file:

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# Check if the operating system is Windows
if(WIN32)
    message("Operating system is Windows")
    # Add Windows-specific commands or set variables here
endif()

# Check if the operating system is Linux
if(UNIX AND NOT APPLE)
    message("Operating system is Linux")
    # Add Linux-specific commands or set variables here
endif()

# Check if using GNU compiler
if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
    message("Using GNU compiler")
    # Add commands specific to GNU compiler here
endif()

In the above example, the if statements check different conditions such as the operating system and compiler being used, and execute certain commands or set variables based on those conditions. You can customize the conditions and actions inside the if blocks to suit your specific needs.

How to build a project using cmake command line?

To build a project using CMake command line, you can follow these steps:

1. Create a new directory for your project and navigate to it in your terminal.
2. Create a CMakeLists.txt file in the root directory of your project. This file will contain the instructions for building your project.
3. Add your project's source files to the project directory, if you haven't already done so.
4. Run the following command in your terminal to generate the build files using CMake:

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cmake .

This command will generate the necessary files for building your project using the default settings.

1. Once the build files have been generated, you can build your project by running the following command:

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cmake --build .

This command will compile and build your project using the generated build files.

1. If you want to specify a different build type (e.g. Release, Debug) or other options, you can pass these options to the cmake command when generating the build files:

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cmake -DCMAKE_BUILD_TYPE=Release .

You can also specify other options such as the output directory, compiler flags, etc. by passing additional options to the cmake command.

1. Once the build process is complete, you will find your compiled project executable in the build directory (e.g. ./build/).

By following these steps, you can build your project using CMake command line.

What is the difference between add_executable and add_library in cmake?

In CMake, add_executable is used to create an executable binary file from source files, such as C++ source files. It links the source files together to create the final executable that can be run by the user.

On the other hand, add_library is used to create a library file from source files, such as C++ source files. This library file can be linked with other executable files or libraries to provide reusable code and functionality.

In summary, the main difference is that add_executable creates an executable binary file, while add_library creates a library file.