need help to passing argument to executable and get return the result

[ashwani]

hi monks,
i just started learning perl and i'm trying to make an application. and i'm stuck to proceed.
well my requirement is
a simple cgi script having a html page contain a text box and button.
there is one more application hello.pl
when i pass a value in text box and press button then this cgi script should pass this textbox value to hello.pl
hello.pl should accept that value and should prepare this

<greet>//here text box value//</greet>

and hello.pl should return this to cgi script which should show that
text box ,button and that return value below the button.
if i made executable of hello.pl using pdk
then i'm stuck at how to pass that value to hello.exe and
how can i get that return value in cgi and can proceed.
i need to done it.
Thanks in Advance