Linux中的PATH环境变量

Question

我想知道 linux 操作系统给出的标准环境变量如 PATH、HOME 是如何自动设置的。这些是从哪个文件中读取的。当特定用户登录时，应该有一些文件从中设置这些变量。

Answer 1

您的问题的答案可以在INVOCATION部分找到man bash。这是相关的摘录：

   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.

手册页中还有更多内容，我建议您阅读它。