Linux and Proxy setting notes

Linux & proxy settings are always very bothersome to search.

[apt-get] export command or set as a environmental variable
export http_proxy=http://[address]:[port]/

[wget] xport command or set as a environmental variable
export http_proxy=http://[address]:[port]/

[yum] 環xport command or set as a environmental variable
export http_proxy=http://[address]:[port]/

[rpm] use command line options
rpm --httpproxy [address] --httpport [port]