shell设置http_proxy

root@bananapi /home/pi # export http_proxy=http://172.93.36.118:8088
root@bananapi /home/pi # export http_proxy
root@bananapi /home/pi #
root@bananapi /home/pi # curl https://ip.cn
当前 IP：172.93.36.118 来自：美国
root@bananapi /home/pi # unset http_proxy
root@bananapi /home/pi # export http_proxy
root@bananapi /home/pi # curl https://ip.cn
当前 IP：114.95.130.194 来自：上海市 电信