You can find out the version of the Korn shell (ksh) on a Linux or Unix-like system using the following command:
ksh -c 'echo $KSH_VERSION'
This command runs a simple echo command in ksh, and uses the KSH_VERSION environment variable to print the version of the shell.
Alternatively, you can use the following command to print the version information:
ksh --version
This command will display a message that includes the version number, along with other information about the shell.
Note that the version of ksh that is installed on your system may be different from other systems, depending on the distribution and version of Linux or Unix that you are using.