Configuration file sequence for bash.

see : www.gnu.org/software/bash/manual/html_node/Bash-Startup-Files.html


Login configuration 

/etc/profile 

  
system wide configuration
  
automaticly read on login from terminal
  
configures minimal defaults : prompt, path, etc.
  
may read additional default resource files if told to.
  

     
Our system is configured to read :
     
/etc/bash.bashrc
     
files in /etc/profile.d (system specific?), 
  


$HOME/.bash_profile

  
User specific profile
  
automaticly read on successful login from terminal
  
Only read on login or if a shell is started with --login.
  
If .bash_profile not found, system will to run the 1st of the following
    two alternatives it finds.
      $HOME/.bash_login
      $HOME/.profile
  
May source .bashrc, a local resource file, or others.



Non login interactive shell configuration

/etc/bash.bashrc

  
system wide configuration
  
automaticly read when a non-login interactive shell is started.
  
Or if called by /etc/profile


$HOME/.bashrc 

  
read for non-login instances of shell startup.
    e.g scp, sftp, invoking bash from command line.
  
Shouldn't contain standard output, eg. echo 
  
Shouldn't contain aliases that redefine standard commands to
     be interactive unless conditionally assigned if PS1 defined.


$BASH_ENV

  
May be assigned a resource file which is invoked when a non-interactive
    bash shell is started, such as a shell script.
  
Shouldn't contain standard output, eg. echo 



Logout 

$HOME/.logout

  
read on logout.
  
Can be used to reset or clean up login.



It is common to have the login configuration files invoke the non-login
interactive configuration files as part of the login process.

Examples :

  /etc/profile
  ~/.bash_profile
  /etc/bash.bashrc
  ~/.bashrc