This header allows you to annotate your code so external tools know about dynamic shared library dependencies.

If you determine that your toolchain doesn't support dlopen notes, you can disable this feature by defining SDL_DISABLE_DLOPEN_NOTES. You can use this CMake snippet to check for support:

Use this macro with SDL_ELF_NOTE_DLOPEN() to note that a dynamic shared library dependency is optional.

    include(CheckCSourceCompiles)
    find_package(SDL3 REQUIRED CONFIG COMPONENTS Headers)
    list(APPEND CMAKE_REQUIRED_LIBRARIES SDL3::Headers)
    check_c_source_compiles([==[
      #include <SDL3/SDL_dlopennote.h>
      SDL_ELF_NOTE_DLOPEN("sdl-video",
        "Support for video through SDL",
        SDL_ELF_NOTE_DLOPEN_PRIORITY_SUGGESTED,
        "libSDL-1.2.so.0", "libSDL-2.0.so.0", "libSDL3.so.0"
      )
      int main(int argc, char *argv[]) {
        return argc + argv[0][1];
      }
    ]==] COMPILER_SUPPORTS_SDL_ELF_NOTE_DLOPEN)
    if(NOT COMPILER_SUPPORTS_SDL_ELF_NOTE_DLOPEN)
      add_compile_definitions(-DSDL_DISABLE_DLOPEN_NOTE)
    endif()
    

Optional functionality uses the dependency, the binary will work and the dependency is only needed for full-featured installations.

See also

SDL_ELF_NOTE_DLOPEN, sDL_ELF_NOTE_DLOPEN_PRIORITY_RECOMMENDED, sDL_ELF_NOTE_DLOPEN_PRIORITY_REQUIRED

FFI conventions

Unsuffixed aliases are unsafe foreign imports; aliases suffixed Safe are safe. Functions whose callbacks fire during the call export only the Safe alias (the genuine unsafe import stays reachable under SDL3.Sys.Bindgen.Dlopennote.Unsafe); functions curated unsafe-only export only the unsuffixed one. Each alias's documentation records its flavor and rationale.

Full conventions: SDL3.Sys.

Since: 3.4.0