.env file
A fourth file that the operating system uses at login time is the .env file,
if your .profile contains the following line: export
ENV=$HOME/.env
The .env file lets you customize your individual working environment variables. Because the .env file is hidden, use the ls -a command to list it. For more information about the ls command, see ls. The .env file contains the individual user environment variables that override the variables set in the /etc/environment file. You can customize your environment variables as desired by modifying your .env file.
The following example is a typical .env file:
export myid=`id | sed -n -e 's/).*$//' -e 's/^.*(//p'`
#set prompt: login & system name & path
if [ $myid = root ]
then typeset -x PSCH='#:\${PWD}> '
PS1="#:\${PWD}> "
else typeset -x PSCH='>'
PS1="$LOGNAME@$UNAME:\${PWD}> "
PS2=">"
PS3="#?"
fi
export PS1 PS2 PS3
#setup my command aliases
alias ls="/bin/ls -CF" \
d="/bin/ls -Fal | pg" \
rm="/bin/rm -i" \
up="cd .."
Note: When modifying the .env file, ensure that newly
created environment variables do not conflict with standard variables such
as MAIL, PS1, PS2,
and IFS.