UNIX / Linux: Set your PATH Variable Using set or export Command

Posted on in Categories , , , , last updated October 5, 2013

How do I add a new path to $PATH variable under Linux and UNIX like operating system? What is my path, and how do I set or modify it using csh/tcsh or bash/ksh/sh shell?

The PATH is an environment variable. It is a colon delimited list of directories that your shell searches through when you enter a command. All executables are kept in different directories on the Linux and Unix like operating systems.

Finding out your current path

To find out what your current path setting, type the following command at shell prompt. Open the Terminal and then enter:

echo "$PATH"

OR

printf "%s\n" "$PATH"

Sample outputs:

/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/X11/bin:/usr/local/sbin/modemZapp:/Users/vivek/gcutil-1.8.4

How do I modify my path?

To modify your path edit $PATH variable as per your shell. The syntax for setting path under UNIX / Linux dependent upon your login shell.

Bash, Sh, Ksh shell syntax to modify $PATH

If you are using bash, sh, or ksh, at the shell prompt, type:

## please note 'PATH' is CASE sensitivity and must be in UPPERCASE ##
export PATH=$PATH:/path/to/dir1
export PATH=$PATH:/path/to/dir1:/path/to/dir2

OR

## please note 'PATH' is CASE sensitivity and must be in UPPERCASE ##
PATH=$PATH:/path/to/dir1; export PATH

Please feel free to replace /path/to/dir1 with the directory you want the shell to search.

Tcsh or csh shell syntax to modify $PATH

If you are using tcsh or csh, shell enter:

 ## please note 'path' is case sensitivity and must be in lowercase ##
set path = ($path /path/to/dir1)
set path = ($path /path/to/dir1 /path/to/dir2)

OR

## please note 'PATH' is CASE sensitivity and must be in UPPERCASE ##
setenv PATH $PATH:/path/to/dir1
setenv PATH $PATH:/path/to/dir1:/path/to/dir2

Please feel free to replace /path/to/dir1 with the directory you want the shell to search.

Examples

In this example add /usr/local/bin to your path under BASH/ksh/sh shell, enter:

export PATH=$PATH:/usr/local/bin

OR

PATH=$PATH:/usr/local/bin; export PATH

To make these changes permanent, add the commands described above to the end of your ~/.profile file for sh and ksh shell, or ~/.bash_profile file for bash shell:

## BASH SHELL ##
echo 'export PATH=$PATH:/usr/local/bin'  >> ~/.bash_profile

KSH/sh shell user try:

## KSH / SH SHELL ##
echo 'export PATH=$PATH:/usr/local/bin'  >> ~/.profile

In this final example add /usr/local/bin/ and /scripts/admin/ to your path under csh / tcsh shell, enter:

set path = ($path /usr/local/bin /scripts/admin)

OR

setenv PATH $PATH:/usr/local/bin:/scripts/admin

To make these changes permanent, add the commands described above to the end of your ~/.cshrc file:

echo 'set path = ($path /usr/local/bin /scripts/admin)'  >> ~/.cshrc

OR

echo 'setenv PATH $PATH:/usr/local/bin:/scripts/admin'  >> ~/.cshrc

To verify new path settings, enter:
$ echo $PATH

See also
  • Man pages – bash(1),ksh(1),csh(1),tcsh(1)

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin and a trainer for the Linux operating system/Unix shell scripting. He has worked with global clients and in various industries, including IT, education, defense and space research, and the nonprofit sector. Follow him on Twitter, Facebook, Google+.

Share this on (or read 21 comments/add one below):

21 comment

  1. Hello,

    I am a newbie on Linux.

    I would like to ask if I can include an environment variable (e.g. ARCHIVES) that points to a directory (e.g. EXPORT ARCHIVES=/some/path/directory) to the .bash_profile, so that I dont do exporting all the time, everytime I need to use the directory?

    regards,
    Giovanni

    Reply Report comment

  3. Or add as follows to your .bashrc file:
    “echo ‘export PATH=$PATH:/usr/local/bin’ >> ~/.bashrc”

    Isn’t echo ” ‘PATH=$PATH:/usr/local/bin’ >> ~/.bashrc ” a better idea?

    Reply Report comment

    1. Hi,
      To remove a path, go to”File System”. Open
      /etc folder and edit (that is, remove )the path from the ‘environment’ text file. You can edit using the sudo command. Following are the commands.
      cd ~
      cd etc
      sudo gedit environment

      After removing the path from the “environment” file, save and restart the machine

      Reply Report comment

      1. Hi,
        There was one mistake. It is “cd /”, not “cd ~”
        To remove a path, go to”File System”. Open
        /etc folder and edit (that is, remove )the path from the ‘environment’ text file. You can edit using the sudo command. Following are the commands.
        cd /
        cd etc
        sudo gedit environment

        After removing the path from the “environment” file, save and restart the machine

        Reply Report comment

  5. To add a PATH for any user with sh or bash shell permanantly use the following steps.

    1. Create a new file .profile in root(/) directory.
    2. Add the following lines into it
    PATH= path to enter
    export PATH
    3.save the file
    4.exit and login to server again
    5.check using echo $PATH

    IT will work. Please let me know if tou have any queries on this !!!

    Sreejith

    Reply Report comment

  6. When I run my program I get this result:
    terminate called after throwing an instance of ‘std::logic_error’
    what(): basic_string::_S_construct NULL not valid
    Aborted

    Is this a result of having the wrong environment variable on my path or what. The program compiles without any errors. This is happening on Ubuntu (Linux, OS 10.0)

    Reply Report comment

  8. Hi there, thanks fo the article!

    FYI, I just tried the syntax above for a tcsh but it didn’t work.
    This works:

    setenv PATH ${PATH}:${HOME}/bin:.

    (Include this line directly in your .cshrc file. This example adds a dir called ~/bin and your current dir to the previously existing PATH)

    (Or, if you don’t want to open and edit your ~/.cshrc file, type this in a teminal:)

    echo 'setenv PATH ${PATH}:${HOME}/bin:.' >> ~/.cshrc
    Reply Report comment

    1. Hi,

      Thanks for the heads up. The faq has been updated with correct syntax. FYI, the syntax setenv PATH ${PATH}:${HOME}/bin:. can be updated using the following syntax too:

       ## please note 'path' is case sensitivity and must be in lowercase ##
set path = ($path $HOME/bin .)
echo $path
echo $PATH

      Appreciate your post.

      Reply Report comment

  10. Hi :
    I am new to linux.
    May I ask how to convert this bash to tcsh?

    #remove faulty version of Makefile from $PATH
export PATH$(echo $PATH | tr `:` `\n` | awk `$0 != "/usr/local/bin"` | paste -sd:)

    Best Regards,
    McGrady

    Reply Report comment

  12. why would this code be on my computer in a install file with along with macports pubkey and several other files?????

    # $Id: setupenv.bash.in 99822 2012-11-18 11:20:14Z [email protected] $

function export_path() {
    local binpath="/opt/local/bin"
    local sbinpath="/opt/local/sbin"

    local IFS=":"
    local p

    for p in $PATH; do
        if [ "$p" == "$binpath" ]; then
            binpath=""
        elif [ "$p" == "$sbinpath" ]; then
            sbinpath=""
        fi
    done

    if [ -n "$binpath" ]; then
        binpath+=":"
    fi

    if [ -n "$sbinpath" ]; then
        sbinpath+=":"
    fi

    export PATH="${binpath}${sbinpath}${PATH}"
}

function export_manpath() {
    local mpath="/opt/local/share/man"
    local IFS=":"
    local p

    if [ -z "$MANPATH" ]; then
        return
    fi

    for p in $MANPATH; do
        if [ "$p" == "$mpath" ]; then
            mpath=""
        fi
    done

    if [ -n "$mpath" ]; then
        mpath+=":"
    fi

    export MANPATH="${mpath}${MANPATH}"
}

function export_display() {
    if [ -z "$DISPLAY" ]; then
        export DISPLAY=":0.0"
    fi
}

export_path
export_manpath
export_display

# Remove defined functions to prevent them from cluttering the shell,
# but they are needed to restrict variables to the local scope
unset export_path
unset export_manpath
unset export_display
    Reply Report comment

  15. I have a machine that is running on kernel 2.6.32-504.16.2.el6.x86_64, I want to build a custom kernel using the same kernel on the same machine, but when I run make menuconfig, I get the following error

    *** Unable to find the ncurses libraries or the
    *** required header files.
    *** ‘make menuconfig’ requires the ncurses libraries.
    ***
    *** Install ncurses (ncurses-devel) and try again.
    ***
    make[1]: *** [scripts/kconfig/dochecklxdialog] Error 1
    make: *** [menuconfig] Error 2

    I have the ncurses installed already in /lib64 and modified my PATH to point to /lib64, but I still get the same error, it looks like that it can not be found. does anyone have an idea why this is not working?

    Reply Report comment

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