https://www.cnblogs.com/wangmo/p/7205528.html
yum install -y git scons gcc gcc-c++ openssl check cmake bison boost-devel asio-devel libaio-devel ncurses-devel readline-devel pam-devel socat
yum install --downloadonly --downloaddir=/root/pxc git scons gcc gcc-c++ openssl check cmake bison boost-devel asio-devel libaio-devel ncurses-devel readline-devel pam-devel socat