Hi ,
I do have a line in my code as follows:

if [[ -z $FILE_NAME ]] ; then
...
else
...
fi

What does the -z does ? Similarly there is -s in some other part of the code. I guess there are many options like this.. Can anybody please tell what all options are available and what do they mean ?

The statement means "if the variable $FILE_NAME is of zero length, then...".
The -s option could mean anything, depending on where it is used.
Check out http://www.tldp.org/LDP/Bash-Beginners-Guide/html/ for a place to start learning shell scripting. If it is bash You want to learn about.

Hi Lakris,

Thanks for your help.