Csdrhrt

This is very simple. Run sudo -l. This will list any sudo privileges you have.

Here is the script-friendly version:

timeout 2 sudo id && echo Access granted || echo Access denied

since it won't stuck on the password input if you do not have the sudo access.

You can also set it in a variable like:

timeout 2 sudo id && sudo="true" || sudo="false"

echo "$sudo"

^{Note: On macOS, you need to install coreutils, e.g. brew install coreutils.}

For me, 'sudo -v' and 'sudo -l' did not work in a script because sometimes interactive (asking me for a password, like mentioned above).
'sudo -n -l' did also not work, it gave the exit code '1' although I have sudo permissions, because of the missing password.
But extending the command to:

A=$(sudo -n -v 2>&1);test -z "$A" || echo $A|grep -q asswor

was successful for me for the script.
This expression gives 0 if the current user can call 'sudo' and 1 if not.

Explanation:

The additional parameter -n to sudo prevents interactivity.

The output $A of the command 'sudo -n -v 2>&1' may be:

- empty (in this case, sudo can be called by the current user), or:

- a note that the current user is not authorized for sudo, or:

- a question text for the password (in this case, the user is authorized).

("asswor" will fit for an english "password" as well as for a German "Passwort").

i've got low rank to vote and comment, but i wanted to upvote Gerald Schade's answer, as i've found that the only way previously, and thought that no1 else knows it - til now :D

btw my solution:

[[ "$(whereis sudo)" == *'/'* && "$(sudo -nv 2>&1)" != 'Sorry, user'* ]]

(from the end of 2015 mwhahaaa)

Gerald Schade's answer here, can still be improved!

Use

prompt=$(sudo -nv 2>&1)

if [ $? -eq 0 ]; then

  # exit code of sudo-command is 0

  echo "has_sudo__pass_set"

elif echo $prompt | grep -q '^sudo:'; then

  echo "has_sudo__needs_pass"

else

  echo "no_sudo"

fi

Here's a complete example of usage in a script:

#!/usr/bin/env bash



is_root () {

    return $(id -u)

}



has_sudo() {

    local prompt



    prompt=$(sudo -nv 2>&1)

    if [ $? -eq 0 ]; then

    echo "has_sudo__pass_set"

    elif echo $prompt | grep -q '^sudo:'; then

    echo "has_sudo__needs_pass"

    else

    echo "no_sudo"

    fi

}



elevate_cmd () {

    local cmd=$@



    HAS_SUDO=$(has_sudo)



    case "$HAS_SUDO" in

    has_sudo__pass_set)

        sudo $cmd

        ;;

    has_sudo__needs_pass)

        echo "Please supply sudo password for the following command: sudo $cmd"

        sudo $cmd

        ;;

    *)

        echo "Please supply root password for the following command: su -c "$cmd""

        su -c "$cmd"

        ;;

    esac

}



if is_root; then

    echo "Error: need to call this script as a normal user, not as root!"

    exit 1

fi





elevate_cmd which adduser

"Sudo access" comes in flavors. Two primary flavors: First you, or a group your a member of, needs to be setup for sudo access in the /etc/sudoers file.

Secondly you need to know your password, or you need to have done a sudo command recently. Recently enough that the timeout hasn't expired. (Fun fact: you can make the time out very long in your sudoer's file.)

I often want to test for the second kind of access in the prolog of a script that will need to sudo some steps. When this check fails I can advise the user he needs to enable the 2nd kind of access before running the script.

bash-3.2$ if sudo -S -p '' echo -n < /dev/null 2> /dev/null ; then echo 'Sudo is enabled.' ; else echo 'Sudo is not enabled' ; fi

Sudo is enabled.

bash-3.2$ sudo -K

bash-3.2$ if sudo -S -p '' echo -n < /dev/null 2> /dev/null ; then echo 'Sudo is enabled.' ; else echo 'Sudo is not enabled' ; fi

Sudo is not enabled

The -S tells sudo to read the password from stdin. The -p sets an empty prompt. The -K clears the second time of access.

Since it sends stderr to /dev/null, it will also check if the user has the first type of sudo access.