paho.mqtt.c-1.3.10交叉编译

mkdir -p build_out
mkdir -p build_out/build_install
cd my_build
cmake ../ -DPAHO_WITH_SSL=TRUE -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc -DOPENSSL_ROOT_DIR=/opt/mylibs/gcc-linaro-5.5.0-2017.10-x86_64_arm-linux-gnueabihf/openssl-1.0.2t/   -DCMAKE_SYSTEM_NAME=Linux -DCMAKE_INSTALL_PREFIX=build_out/build_install
make 
make install