bash startup files

Summary

Interactive login

1. /etc/profile
2. First found of ~/.bash_profile, ~/.bash_login, ~/.profile
   

Interactive non-login

1. /etc/bash.bashrc
2. ~/.bashrc
   

1. Executes file named by BASH_ENV

Interactive login

1. /etc/profile
   

   # /etc/profile: system-wide .profile file for the Bourne shell (sh(1))
   # and Bourne compatible shells (bash(1), ksh(1), ash(1), ...).
   
   if [ -d /etc/profile.d ]; then
     for i in /etc/profile.d/*.sh; do
       if [ -r $i ]; then
         . $i
       fi
     done
     unset i
   fi
   
   if [ "$PS1" ]; then
     if [ "$BASH" ]; then
       PS1='\u@\h:\w\$ '
       if [ -f /etc/bash.bashrc ]; then
           . /etc/bash.bashrc
       fi
     else
       if [ "`id -u`" -eq 0 ]; then
         PS1='# '
       else
         PS1='$ '
       fi
     fi
   fi
   
   umask 022
   

2.  ~/.profile (/home/prototype/default/.profile)
   

   #echo 'erase ^?, kill ^U, intr ^C'
   stty dec
   PATH=/etc:/usr/etc:/usr/ucb:/bin:/usr/bin:/usr/local/bin:.
   export PATH
   export TERM
   

Interactive non-login

1. /etc/bash.bashrc
   

   # System-wide .bashrc file for interactive bash(1) shells.
   
   # To enable the settings / commands in this file for login shells as well,
   # this file has to be sourced in /etc/profile.
   
   # If not running interactively, don't do anything
   [ -z "$PS1" ] && return
   
   #echo " this is /etc/bash.bashrc "
   # check the window size after each command and, if necessary,
   # update the values of LINES and COLUMNS.
   shopt -s checkwinsize
   
   # set variable identifying the chroot you work in (used in the prompt below)
   if [ -z "$debian_chroot" ] && [ -r /etc/debian_chroot ]; then
       debian_chroot=$(cat /etc/debian_chroot)
   fi
   
   # set a fancy prompt (non-color, overwrite the one in /etc/profile)
   PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
   
   # Commented out, don't overwrite xterm -T "title" -n "icontitle" by default.
   # If this is an xterm set the title to user@host:dir
   #case "$TERM" in
   #xterm*|rxvt*)
   #    PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD}\007"'
   #    ;;
   #*)
   #    ;;
   #esac
   
   # enable bash completion in interactive shells
   #if [ -f /etc/bash_completion ]; then
   #    . /etc/bash_completion
   #fi
   
   # sudo hint
   if [ ! -e $HOME/.sudo_as_admin_successful ]; then
       case " $(groups) " in *\ admin\ *)
       if [ -x /usr/bin/sudo ]; then
           cat <<-EOF
           To run a command as administrator (user "root"), use "sudo ".
           See "man sudo_root" for details.
   
           EOF
       fi
       esac
   fi
   
   # if the command-not-found package is installed, use it
   if [ -x /usr/lib/command-not-found ]; then
           function command_not_found_handle {
                   # check because c-n-f could've been removed in the meantime
                   if [ -x /usr/lib/command-not-found ]; then
                      /usr/bin/python /usr/lib/command-not-found -- $1
                      return $?
                   else
                      return 127
                   fi
           }
   fi
   #echo " this  is the end of /etc/bash.bashrc "
   

2. Default ~/.bashrc (/home/prototype/default/.bashrc)
   

1. Executes file named by BASH_ENV

Details

When  bash is invoked as an interactive login shell, or as a non-inter‐
active shell with the --login option, it first reads and executes  com‐
mands  from  the file /etc/profile, if that file exists.  After reading
that file, it looks for ~/.bash_profile, ~/.bash_login, and ~/.profile,
in  that order, and reads and executes commands from the first one that
exists and is readable.  The --noprofile option may be  used  when  the
shell is started to inhibit this behavior.

When  a  login  shell  exits, bash reads and executes commands from the
file ~/.bash_logout, if it exists.

When an interactive shell that is not a login shell  is  started,  bash
reads  and  executes  commands  from /etc/bash.bashrc and ~/.bashrc, if
these files exist.  This may be inhibited by using the  --norc  option.
The  --rcfile  file option will force bash to read and execute commands
from file instead of /etc/bash.bashrc and ~/.bashrc.

When bash is started non-interactively, to  run  a  shell  script,  for
example, it looks for the variable BASH_ENV in the environment, expands
its value if it appears there, and uses the expanded value as the  name
of  a  file to read and execute.  Bash behaves as if the following com‐
mand were executed:
              if [ -n "$BASH_ENV" ]; then . "$BASH_ENV"; fi
but the value of the PATH variable is not used to search for  the  file
name.

If  bash  is  invoked  with  the name sh, it tries to mimic the startup
behavior of historical versions of sh as  closely  as  possible,  while
conforming  to the POSIX standard as well.  When invoked as an interac‐
tive login shell, or a non-interactive shell with the  --login  option,
it  first  attempts  to read and execute commands from /etc/profile and
~/.profile, in that order.  The  --noprofile  option  may  be  used  to
inhibit  this  behavior.  When invoked as an interactive shell with the
name sh, bash looks for the variable ENV, expands its value  if  it  is
defined,  and uses the expanded value as the name of a file to read and
execute.  Since a shell invoked as sh does not attempt to read and exe‐
cute  commands from any other startup files, the --rcfile option has no
effect.  A non-interactive shell invoked with  the  name  sh  does  not
attempt  to  read  any  other  startup files.  When invoked as sh, bash
enters posix mode after the startup files are read.

When bash is started in posix mode, as with the  --posix  command  line
option, it follows the POSIX standard for startup files.  In this mode,
interactive shells expand the ENV variable and commands  are  read  and
executed  from  the  file  whose  name is the expanded value.  No other
startup files are read.

Bash attempts to determine when it is being run  by  the  remote  shell
daemon,  usually  rshd.  If bash determines it is being run by rshd, it
reads and executes commands from  /etc/bash.bashrc  and  ~/.bashrc,  if
these  files exist and are readable.  It will not do this if invoked as
sh.  The --norc option may be used to inhibit this  behavior,  and  the
--rcfile  option may be used to force another file to be read, but rshd
does not generally invoke the shell with those options or allow them to
be specified.

If the shell is started with the effective user (group) id not equal to
the real user (group) id, and the -p option is not supplied, no startup
files are read, shell functions are not inherited from the environment,
the SHELLOPTS variable, if it appears in the environment,  is  ignored,
and the effective user id is set to the real user id.  If the -p option
is supplied at invocation, the startup behavior is the  same,  but  the
effective user id is not reset.