Command line Prompt
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Environmental variables that controls Command line Prompt
PS1 : Controls the format of default command line prompt.
PS2 : Controls the format of second-tier command line prompt.
PS3 : Controls the format of tertiary command line prompt.
- Shell uses default PS1 prompt for initial data entry into shell.
- If we enter a command that requires additional information, shell displays second-tier prompt specified by PS2 .
- To display current settings for prompt use command :
echo $PS1
echo $PS2
- PS3 is used only in shell scripts.
