CODEWITHSUNDEEP
bashshellps1
Rafael
Rafael

Reputation: 133

echo $PS1 in script

Silly question, but since I'm such a newbie at Linux OS, I'm having trouble to make this simple script to echo the result of PS1.

If I type echo $PS1 in bash, it shows me the result, but not in the script. It returns blank.

Example:

#!/bin/bash
ps1=$(echo $PS1) 
echo $ps1

Any tips for a begginer?

Thanks in advance.

Upvotes: 8

Views: 8772

Answers (5)

Pavel Vlasov
Pavel Vlasov

Reputation: 4341

This one doesn't apply -i to the whole script file. Based on @glennjackman's answer:

> ps1=$(bash -ic 'echo $PS1')
> echo $ps1
\n\[\033[92;5;10m\]\w$...

Upvotes: 0

Piyush Pancholi
Piyush Pancholi

Reputation: 13

try this script from the documentation ..this might help you :

PS1 – The value of this parameter is used as the primary prompt string. The default value is \u@\h \W\$ .

$ echo $PS1 Sample output: [\u@\h \W]$

\a : an ASCII bell character (07)
\d : the date in “Weekday Month Date” format (e.g., “Tue May 26”)
\e : an ASCII escape character (033)
\h : the hostname up to the first ‘.’
\H : the hostname
\j : the number of jobs currently managed by the shell
\l : the basename of the shell’s terminal device name
\n : newline
\r : carriage return
\u : the username of the current user
\v : the version of bash (e.g., 2.00)
\V : the release of bash, version + patch level (e.g., 2.00.0)
\w : the current working directory, with $HOME abbreviated with a tilde
\W : the basename of the current working directory, with $HOME abbreviated with a tilde

Examples:

PS1="\d \h $ " Sample output: Sat Jun 02 server $

PS1="[\d \t \u@\h:\w ] $ " Sample output: [Sat Jun 02 14:24:12 vivek@server:~ ] $

Upvotes: -1

glenn jackman
glenn jackman

Reputation: 247192

Other answers are correct. If you add the -i flag to your shebang, that signals bash that it's supposed to be an interactive shell, so it will read your ~/.bashrc -- see https://www.gnu.org/software/bash/manual/bashref.html#Invoking-Bash

#!/bin/bash -i
ps1="$PS1"
echo "$ps1"

Upvotes: 9

chepner
chepner

Reputation: 532303

PS1 is typically not exported, since it is usually defined in .bashrc, which is sourced by every shell that would need PS1. As such, it isn't inherited by the non-interactive shell that executes your script.

Upvotes: 3

glglgl
glglgl

Reputation: 91139

PS1 is a variable which is not "exported", so it is only visible within the shell, but not from any subprocess such as the script's.

Upvotes: 4

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