etc/conf.d/env_whitlist

# /etc/conf.d/env_whitelist:  Environment whitelist for rc-system

# Specify which variables is allowed to be passed from the environment to the
# rc-system.  If it is not set by the environment, then the variable will be
# taken from /etc/profile.env - meaning, if you need to set LANG or such,
# do it in a /etc/env.d/00myownstuff file for example, and run env-update.

# User controlled
LANG
1	# /etc/conf.d/env_whitelist: Environment whitelist for rc-system
2
3	# Specify which variables is allowed to be passed from the environment to the
4	# rc-system. If it is not set by the environment, then the variable will be
5	# taken from /etc/profile.env - meaning, if you need to set LANG or such,
6	# do it in a /etc/env.d/00myownstuff file for example, and run env-update.
7
8	# User controlled
9	LANG