16、Unix Shell Environment: Variables, Commands, and Constructs

Unix Shell Environment: Variables, Commands, and Constructs

1. PS1 Prompt

The PS1 prompt has its own language with special sequences. These sequences can display the command count, current directory, time of day, and more. To learn about these sequences, you can read the “Prompting” section of the Bash or Sh man page.

2. HOME Variable

• Definition and Function : Your home directory is the directory you are placed in when you log on to the system. A special shell variable called HOME is automatically set to this directory upon login.
  • Example:

$ echo $HOME
/users/steve

• Usage : This variable