====== Users: environment and profiles ======

===== User with ksh or ksh93 =====

Which files are read ?

Direct connection to a user
<cli prompt='>'>
[user1@aixb007] /home/user1> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE3=dot_profile_user1
</cli>

Using su from root:
<cli prompt='>'>
[user1@aixb007] /home/user1> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE3=dot_profile_user1
</cli>

Using crontab of the user1:
<cli prompt='>'>
[user1@aixb007] /home/user1> cat crontab.txt
PROFILE1=etc_environment
</cli>

Using sudo with **Defaults:oracle    !env_reset**
<cli prompt='>'>
[oracle@aixb007] /home/oracle> sudo su user1
[oracle@aixb007] /home/oracle> whoami
user1
[oracle@aixb007] /home/oracle> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE4=dot_profile_oracle


[oracle@aixb007] /home/oracle> sudo su - user1
[user1@aixb007] /home/user1> whoami
user1
[user1@aixb007] /home/user1> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE3=dot_profile_user1
</cli>

Using sudo with **Defaults:oracle    env_reset**
<cli prompt='>'>
[oracle@aixb007] /home/oracle> sudo su user1
[oracle@aixb007] /home/oracle> whoami
user1
[oracle@aixb007] /home/oracle> set | grep PROF


[oracle@aixb007] /home/oracle> sudo su - user1
[user1@aixb007] /home/user1> whoami
user1
[user1@aixb007] /home/user1> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE3=dot_profile_user1
</cli>

login as root in ksh(93) and change to bash
<cli prompt='>'>
[root@aixb007] /root> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE5=dot_profile_root
[root@aixb007] /root> bash
[root@aixb007] /root> set | grep PROF
PROFILE1=etc_environment
PROFILE2=etc_profile
PROFILE5=dot_profile_root
PROFILE7=dot_bashrc_root
</cli>

BASH on AIX doesn't use /etc/*bash*, nor ~/.bash_profile, **the only file specific is .bashrc**

===== Change historyfile =====

If you need to adapt your history file depending on changing owner, like su or sudo

Ex of addon to **/etc/profile**
<code>
...

HOSTNAME=$(/usr/bin/hostname -s)
PS1="[\$LOGNAME@\$HOSTNAME]\$PWD# "
export PS1

EDITOR=/usr/bin/vi
export EDITOR

alias ll='ls -lsa'

# duration in sec 900 s = 15 min
TMOUT=7200
TIMEOUT=7200
typeset -r TMOUT
typeset -r TIMEOUT

HISTSIZE=10000
EXTENDED_HISTORY=ON
HISTTIMEFORMAT="%F %T "

histdir=/var/history/${USER}
mkdir -p $histdir
USER1=$(who am i | awk '{print $1}')
if [ "${USER1}" = "" ]
then
  HISTFILE=$histdir/.sh_history_${USER}
else
  HISTFILE=$histdir/.sh_history_${USER1}
fi
export HISTFILE
typeset -r HISTSIZE # put the variable in readonly
typeset -r EXTENDED_HISTORY
typeset -r HISTDATEFMT

trap 1 2 3
</code>