How to set PATH variables

vivekr · 01-16-2006, 06:27 AM

This may be a terribly easy question but being a newbie to the whole Linux stuff... I dont have any other option than asking it openly and accepting frankly my ignorance..

So how to set environment variables in Linux.
I think I have to use set PATH variable..
But I am dont want to take risk..
Also unlike Windows there seems to be many paths...
Will export pathname=PATH1;PATH2; suffice?

Also how to view the current PATHs..

All info regarding environmental variable setiing and manipulating are welcome

Thanks to all

zhelezov · 01-16-2006, 06:39 AM

hi!

Quote:

Also how to view the current PATHs..

Code:

echo $PATH

i prefer storing my custom variables and aliases in a separate file rather than in ~/.bashrc (is bash your login shell?) like ~/.yourvar which is executed upon login. to get this done add this line to ~/.bashrc

Code:

source ~/.yourvar

Quote:

Will export pathname=PATH1;PATH2; suffice?

export like this in your ~/.yourvar or ~/.bashrc ...as you like:

Code:

export PATH=$PATH:/dir1:...:/dirN

as many directories as you need.

thus you'll have N directories ADDED to your PATH variable. easy, isn't it.

cheers,
vlado

*this topic must be in...<calc>...n^N howtos

Dtsazza · 01-16-2006, 07:40 AM

Since you asked about environment variable manipulation in general, I found the set command very useful when I first came across it - it simply prints (to standard out) a list of all the currently active environment variables. Useful for double-checking you've sorted things properly - though I have a feeling it might only work for bash.

And to expand on zhelezov's method to set paths, you can execute that command from a shell, though it will remain active only in that shell and only until the shell is closed (e.g. if you started an xterm, set some variables, closed xterm and then opened xterm again, it'd be a new shell and your custom variables wouldn't be set). Also, the "$PATH:" at the front is not technically necessary (though a good idea) - what it does is substitute your current PATH variable at the start of the right hand side, so dir1,... dirN get added onto the end of your existing path. If you want to explicitly set path to "/home/foo" and nothing else, then

Code:

export PATH=/home/foo

will do exactly that. Of course, in the vast majority of cases, you'll simply want to add another directory onto your existing path, so using the "$PATH:" format is preferable.

xoy · 09-02-2011, 12:56 AM

In Debian like linux configure here:

global for many shells

Code:

/etc/profile
/etc/profile.d/myname.sh

global for bash only

Code:

/etc/bash.bashrc

local for many shells

Code:

~/.profile

local bash only

Code:

~/.bashrc

smilemukul · 04-02-2012, 11:33 AM

Is this possible to modify the env variable as,

export PATH=/home/foo:/bin/ls instead of /bin as I want to define variable path only for /bin/ls ?

Sydney · 04-02-2012, 11:47 AM

Quote:

Originally Posted by smilemukul

Is this possible to modify the env variable as,

export PATH=/home/foo:/bin/ls instead of /bin as I want to define variable path only for /bin/ls ?

Yes but only for that session. You should check out ~/.bash_profile for editing the path in Bash so it will stick.

~ is a notation for the working user's home directory.

chrism01 · 04-02-2012, 06:32 PM

As above, there are many environment variables used for many reasons; to see them try the cmds

Code:

set

env

PATH is just one of many default variables and you can create your own.

Use the above techniques in login files to ensure new definitions are re-created when you login again.
Note that you need the export cmd to push the declarations down to sub-shells, otherwise they only affect current shell.
You cannot push them up the shell tree though ...

Have a read of http://tldp.org/LDP/Bash-Beginners-G...l/chap_03.html

arijan · 06-04-2012, 03:39 AM

I am a bit confused about $PATH variable. It refers to

/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games,

and if I call $PATH should I have all these paths considered? Or how to refer to particular path within $PATH, like only /usr/bin ?

And another thing:

Can I set variable name in the manner the ~/ is for /home/user ?

pixellany · 06-04-2012, 03:50 AM

Quote:

Originally Posted by arijan

I am not sure if this question is set properly, but here it is:

I was wondering how can I create a path that is a reference to full path - like ~/ for /home/user ?

For instance, I would like to have /media/trans500/dl/music referenced by something shorter, something that I can easily type without using clipboard all the time.

Thanks

Just make a soft link.....For example, in your home directory, enter this:

Code:

ln -s /media/trans500/dl/music music

then, to go to that directory, just type "music"

To relate this to the original topic (the PATH env variable), the latter is intended to establish the search path for commands.

arijan · 06-04-2012, 04:03 AM

Quote:

Originally Posted by pixellany

Just make a soft link.....For example, in your home directory, enter this:

Code:

ln -s /media/trans500/dl/music music

then, to go to that directory, just type "music"

To relate this to the original topic (the PATH env variable), the latter is intended to establish the search path for commands.

Thanks!

I apologize for editing my question - I wanted to put it in a different shape...

Ok, the ln is a way around. If I want to put a path to my music folder into let's say playlist conf file. I would than have to write ~/music.
But if I want to have clean path to /media/trans500/dl/music as just music, than ln desn't help. I was wondering if a global variable that refers to this path could be given by setenv and used in conf files or from wherever, like: MUSIC= /media/trans500/dl/music

pixellany · 06-04-2012, 07:35 PM

Code:

[mherring@hering-GTWay ~]$ pwd
/home/mherring
[mherring@hering-GTWay ~]$ export PLAY=/home/mherring/play
[mherring@hering-GTWay play]$ cd /etc/pacman.d
[mherring@hering-GTWay pacman.d]$ cd $PLAY
[mherring@hering-GTWay play]$ pwd
/home/mherring/play