bipinajith was a bit carefree here:

Which OS:

Code:

uname -a

Some OSes (HP-Ux, Solaris) will show the version too this way, some have other commands for this:

Which ksh-version:
I am not sure if every ksh version understands this - the AIX version doesn't, for instance. The "--" to introduce worded options is a Linux speciality and not common everywhere. What is guaranteed to work is:

Code:

print - ${.sh.version}

or

Code:

set -o vi
<ESC><^V>

I hope this helps.

bakunin