LinuxのPATH環境変数

あなたの質問に対する答えはセクションにありINVOCATIONますman bash。関連する抜粋は次のとおりです。

   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 ~/.bashrc, if that file exists.  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
   ~/.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.

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