PS1 customizing prompt.

commandline session

jeffrin@debian:~$ PS1=" $ s # "
 $ bash 2 PS1=" $ V # "
 $ 4.2.20 3 PS1=" $ V # ! "
 $ 4.2.20 4 341 PS1="[ 33[0;41m]$[ 33[0m] "
$
$ ARCH
bash: ARCH: command not found
$ arch
x86_64
$ PS1="[ 33[0;41m]$[ 33[0m] "
$ PS1=" $ V # ! "
 $ 4.2.20 9 346 arch
x86_64
 $ 4.2.20 10 347 PS1="[ 33[0;31m] $ V # ! "
 $ 4.2.20 11 348