how can i set evironment variable permenantly in path

any help will be highly appreciated

thanks & best regards

If I understand your question this would do it for the bash shell.
That readonly directive makes the PATH variable permanent at whatever you set it to. The example is making the PATH variable permanently set to whatever it was already set to.

I believe you can edit /etc/bash.bashrc or your local .bashrc, add the following line:
export PATH=PATH,/your/new/path

That should add your new path onto your existing one, rather than clobbering it. That's just off the top of my head; tere may be a better way.

and how can I edit mean to say delete something from path??

but how'll i edit

edit /etcbash.bashrc ??

Once the variable is readonly you cannot change it. If you want something different than the system default then you have to specify what you want.

If you wanted your PATH variable to be /bin:/usr/bin then you would put this in your /etc/bashrc or in your user account's ~/.bashrc.
If you want that to be readonly then you would use the readonly directive as follows.

You edit the file with a text editor. If you want to edit /etc/bash.bashrc (the file may be /etc/bashrc or something different though), you'll need to be root. Obviously if you want to edit the .bashrc in your home directory, you won't need root priviliges.

I didn't know this readonly command!

Unless for specific need, this should not been put in bashrc.

.bashrc is executed for each subshells.

So you login, /etc/profile is executed only once
->PATH=/bin
You open a terminal in your wm for example, bashrc is executed
->PATH=/bin:/your/new/path
In this terminal you open an subshell (like running any script would do) :
$bash
->PATH=/bin:/your/new/path:/your/new/path

Solution is to put it in a profile file (/etc/profile for example)

this is the main problem with me as I am begginer and have novoice to edit the file.

you mentioned "text editor" could you plz be more specific

Thanks & best regards

There are many editors avail on Linux.
Pls add your distribution ie Linux name eg Rh Fedora Core, Suse, Debain, whatever to your profile info (info under your name on posts).
Aslo, add your dektop environment ie KDE or Gnome (probably one of those).
anyway, some editores include:
vi, vim, kedit, gedit, kate, nano, pico etc ....
You'll need to learn at least one of those.
The editor that's avail on all Unix style systems is vi, and a lot these days have the option of vim (means vi improved).
Others may or may not be available.