I have two servers one AIX with default shell ksh, the other RHEL with default shell bash.

I have a script that is mounted on both that will run similar commands but for either AIX or Linux. This script does not work on the bash servers, is there a way to make this script run on both bash and ksh, or would the best option be to create two different scripts?

#!/usr/bin/ksh
export OS=`uname -s`
echo "OS is "$OS"."
case $OS in
        "AIX")
                #run AIX commands;;
        "Linux")
                #run Linux commands;;
        "*")
                echo "Exiting. The OS type is not found.";;
esac
echo "Done."
exit 0

I have two servers one AIX with default shell ksh, the other RHEL with default shell bash.

I have a script that is mounted on both that will run similar commands but for either AIX or Linux. This script does not work on the bash servers, is there a way to make this script run on both bash and ksh, or would the best option be to create two different scripts?

#!/usr/bin/ksh
export OS=`uname -s`
echo "OS is "$OS"."
case $OS in
        "AIX")
                #run AIX commands;;
        "Linux")
                #run Linux commands;;
        "*")
                echo "Exiting. The OS type is not found.";;
esac
echo "Done."
exit 0

UPDATE

The commands I need to run are for user accounts on each server. An example of unlocking an account. AIX /usr/bin/chuser account_locked=false $USERNAME

Linux /usr/bin/passwd -u $USERNAME

Through further investigation I have found that the the shells location in AIX are located at /usr/bin/sh, while Redhat's are located at /bin/sh.

Can I define the shebang based on the results of "uname"?