Running external commands from a Custom GUI in C#

for one of my applications, I am trying to sen开发者_StackOverflow社区d/receive commands/information from my GUI application to the cmd window.

There is one problem however.. I also have a perl installation which I need to work with. the problem is when I try perl -v in the cmd window the cmd window reacts with the perl version message. When i try it my GUI it comes up with the message

'perl' is not recognized as an internal or external command, operable program or batch file.

Please suggest..

Update

Restarting my machine solved that issue. I really dont know what was the issue with the path variables..

New Question, Please

I have a sample perl script that waits for a user response and then starts acting on the input provided. It behaves as it should in the cmd window., but when it comes to my GUI.. it does not wait for the user input.. There is an endless looop and it keeps on printing the message to my UI..

Any help would be highly appreciated..

Thanks and Regards Gagan Janjua

Restarting my application seems to have fixed my issue...

thanks @RedGrittyBrick.. I will remember the tip...