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

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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.

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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 – tcsh(1)

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Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.

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

  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?

    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

      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

  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

  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)

  7. Hi ,

    Could any one explain me about the functionality of command in shell script
    set -xv
    . /opt/app/etl/bin/profile.ksh
    . `dirname $0`/env.cfg

    1. Hi Sumanth,

      Print input commands and their arguments as they are executed –> when you use set -xv

  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

    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.

  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

  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 raimue@macports.org $

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

  13. SET doesn’t seem to do anything.
    PATH as a variable name is case sensitive by me, but in this tut, this gets ignored.
    Very bad. Didn’t helped me at all.

  14. hello,

    by mistake i changed defaults PATH ,how can i get default PATH from command line
    i can’t even vi that hiden files

    please help

    Thanks

  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?

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