if(UNIX)
    # file1 => file2 => file3 (real)

    set(bindir ${CMAKE_CURRENT_BINARY_DIR})

    file(WRITE ${bindir}/file3 "test file")
    find_program(LN NAMES "ln")

    if(LN)
        # Create symlinks using "ln -s"
        if(NOT EXISTS ${bindir}/file2)
            execute_process(COMMAND ${LN} "-s" "${bindir}/file3" "${bindir}/file2")
        endif()
        if(NOT EXISTS ${bindir}/file1)
            execute_process(COMMAND ${LN} "-s" "${bindir}/file2" "${bindir}/file1")
        endif()

        get_filename_component(file1 ${bindir}/file1 ABSOLUTE)
        get_filename_component(file2 ${bindir}/file2 ABSOLUTE)
        get_filename_component(file3 ${bindir}/file3 ABSOLUTE)

        if(NOT file3 STREQUAL "${bindir}/file3")
            message(FATAL_ERROR "CMake fails resolving absolute file file3")
        endif()

        if(NOT file2 STREQUAL "${bindir}/file3")
            message(FATAL_ERROR "CMake fails resolving simple symlink")
        endif()

        if(NOT file1 STREQUAL "${bindir}/file3")
            message(FATAL_ERROR "CMake fails resolving double symlink")
        endif()

        # cleanup
        file(REMOVE ${bindir}/file1)
        file(REMOVE ${bindir}/file2)
        file(REMOVE ${bindir}/file3)
        if(EXISTS file1 OR EXISTS file2 OR EXISTS file3)
           message(FATAL_ERROR "removal of file1, file2, or file3 failed")
        endif()

    endif(LN)
endif()