By default rules for (un)setting of variables is taken from the config file /etc/security/pam_env.conf if no other file is specified.
This module can also parse a file with simple KEY=VAL pairs on separate lines (/etc/environment by default). You can change the default file to parse, with the envfile flag and turn it on or off by setting the readenv flag to 1 or 0 respectively.
Since setting of PAM environment variables can have side effects to other modules, this module should be the last one on the stack.
The auth and session module types are provided.
pam_env.conf(5), pam.d(5), pam(7).
pam_env was written by Dave Kinchlea <email@example.com>.