Use printenv

# printenv
TERM=screen
SHELL=/bin/bash
SSH_CLIENT=10.171.0.141 60941 22
SSH_TTY=/dev/pts/0
USER=root
MAIL=/var/mail/root
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
PWD=/etc/pam.d
LANG=en_US.UTF-8
SHLVL=1
HOME=/root
LOGNAME=root
SSH_CONNECTION=10.171.0.141 60941 10.122.0.33 22
_=/usr/bin/printenv
OLDPWD=/etc
#