1

I created a bash script to add /My_Scripts/Bash_Scripts to the default PATH of linux.

!/bin/bash
#This Script is used to add a folder/diectory to the PATH..


echo -e "\e[92m\e[1mCREATING PATH...........\n\n"
cd
mkdir My_Scripts
cd My_Scripts
mkdir Bash_Scripts
cd

export PATH=$PATH:$HOME/My_Scripts/Bash_Scripts
echo -e "\e[92m\e[1mPATH CREATON SUCCESSFUL\n \e[39m"
echo $PATH

The output of script is

root@kali:~/Desktop# bash add_path
CREATING PATH...........


PATH CREATON SUCCESSFUL

`/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/root/My_Scripts/Bash_Scripts'

but if I type echo $PATH in the terminal outside, the path is not added

root@kali:~/Desktop# $PATH
bash: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin: No such file or directory
Tunaki
  • 132,869
  • 46
  • 340
  • 423
RoY
  • 113
  • 1
  • 4
  • 14

3 Answers3

1

Your changes is affected in current shell only.Put the entry in .bashrc file. It will affect the all the terminal.open the .bashrc file and add the below line and run the file -

 vim ~/.bashrc
 export PATH="$PATH:/home/username"
 ~/.bashrc

Edit the parent shell

script.sh

#!/bin/bash 
export "PATH=$PATH:$HOME/My_Scripts/Bash_Scripts"
echo $PATH

$~ PATH=$(./script.sh)

$~ echo $PATH

/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/loganaayahee/My_Scripts/Bash_Scripts
loganaayahee
  • 809
  • 2
  • 8
  • 13
1

You are starting up a new bash process and PATH is only modified in the context of the new process. When this process quits, changes done in its environment do not propagate to the parent process.

Instead, you would want to modify PATH in the context of current bash process. If you want this temporarily, you may source your script. source will run in the context of the current bash process. Beware of any side effects - like cd will change the directory, exit will terminate the current bash process.

If you want this change permanently for all future interactive sessions, you can modify ~/.bashrc.

Also, the syntax of shebang is #!/path/to/program, you are missing a #.

Gowtham
  • 1,465
  • 1
  • 15
  • 26
  • Thank you for replying.. Now that i know what caused the problem. Can u please tell me what changes should i make in the script so that i can use it permanently for future interactive sessions.. – RoY Oct 31 '15 at 10:46
  • Include `export PATH=$PATH:$HOME/My_Scripts/Bash_Scripts` in your .bashrc. – Gowtham Oct 31 '15 at 10:50
  • sir i am new to bash programming ..can u please tell me the whole script – RoY Oct 31 '15 at 10:53
  • Everyone starts new. See https://www.gnu.org/software/bash/manual/html_node/Bash-Startup-Files.html and google is your best friend :) – Gowtham Oct 31 '15 at 10:55
  • 1
    sir no luck in googling it so can u please write a bash script which copies /My_Scripts/Bash_Scripts to .bashrc – RoY Oct 31 '15 at 11:02
0

First thing - you should use echo $PATH. By simply typing $PATH you're trying to execute the command, hence the "No such file or directory error"

Next - the /root/My_Scripts/Bash_Scripts wasn't really added to the PATH. The first output you see in done inside the script, so the changes could be seen there.

The reason is that PATH will be set only in the context of the script shell, execute it as source add_path to preserve the changes in variables (but only for current shell).

If you want the variable to be persistant in all shells - add it to /.bashrc (since you're runnung as root).

Roman Pustylnikov
  • 1,937
  • 1
  • 10
  • 18
  • Thank you for replying ... Now i seem to understand the problem.. But i dont know how to automate it.. Can U Please tell me what changes i have to make in my script to automate it – RoY Oct 31 '15 at 10:49
  • Append it to some file and source this file (or export from it) in your .bashrc script. This way the change will be permanent – Roman Pustylnikov Oct 31 '15 at 10:55
  • Sir i am new to bash. and i dont know how to do it... so can u please write a bash script which copies /My_Scripts/Bash_Scripts to .bashrc – RoY Oct 31 '15 at 11:00
  • It seems you have installed Kali linux. If it was on purpose - you kinda need to learn bash and linux basics first before you proceed. So I higly recommend you to look into the manuals and to try things by yourself. – Roman Pustylnikov Oct 31 '15 at 11:51