Thanks for your help in previous post :) As you can see in this script snippet, I redirected the powershell STDOUT to a file. It's not the exact solution of my earlier problem but, it's just a workaround.
In my earlier post I wanted to store the powershell script output in a variable. It didn't work using open2 function. So, to move ahead with my objective in a faster way, I used this workaround. Now, here again as you see, I found a trouble :) This time my powershell script invoked a browser, where I need to put my credential and click on the validation button.
Here, I think I can solve this problem in two ways, either modify the powershell code itself or find a way in perl to handle it. First way to modify powershell script seems reluctant to me as it would require powershell knowledge and also modification in the existing scripts (this thing I want to avoid). Second way is good as it would enhance my Perl skills and I would love that :)