修改CMakelists文件

cmake_minimum_required(VERSION 3.17)
project(mutex_learn)set(CMAKE_CXX_STANDARD 14)set(BOOST_ROOT "/usr/local/include/boost")
#添加头文件搜索路径
include_directories(/usr/local/include)
#添加库文件搜索路径
link_directories(/usr/local/lib)add_executable(mutex_learn main.cpp)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
#set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -lrt")target_link_libraries(mutex_learn boost_thread boost_system rt)

• 最核心的是最后一句话target_link_libraries(mutex_learn boost_thread boost_system rt)，在target_link_libraries后面加入rt即可解决问题